Kosice Chemistry Flashcards by Mary Loughlin

The number of lone pairs in the molecule of water is:
A) 0
B) 1
C) 2
D) 3

C) 2

How well did you know this?

Not at all

Perfectly

What is the oxidation number of carbon in K2CO3 :

How well did you know this?

Not at all

Perfectly

Express the following quantity in milligrams: 2Kg

2,000,000mg

How well did you know this?

Not at all

Perfectly

The only Liquid Metal is:
A) He
B) Ge
C) Hg
D) H

C) Hg

How well did you know this?

Not at all

Perfectly

Which of the following is a noble gas?
A) Carbon
B) Oxygen
C) Sodium
D) Neon

D) Neon

How well did you know this?

Not at all

Perfectly

Isomers share the same:
A) reactivity
B) molar mass
C) solubility
D) boiling point

B) molar mass

How well did you know this?

Not at all

Perfectly

What is a component of ant venom?
A) methanol
B) acetic acid
C) 2-propanol
D) formic acid

D) formic acid

How well did you know this?

Not at all

Perfectly

An anion is a ____ charged ion.

Negative

How well did you know this?

Not at all

Perfectly

Which of the following substances is a pure compound?
A) sea water
B) glucose
C) steel
D) air

B) glucose

How well did you know this?

Not at all

Perfectly

Sublimation involves a change from:
A) solid to a gas
B) liquid to a gas
C) gas to a liquid
D) gas to a solid

A) solid to a gas

How well did you know this?

Not at all

Perfectly

Compounds of this halogen are used as additives in toothpastes:
A) Fe
B) F
C) Cl
D) Cr

B) F

How well did you know this?

Not at all

Perfectly

In a solution of salt and water, the solute is the:

Salt

How well did you know this?

Not at all

Perfectly

All of the following are heterogeneous mixtures except:
A) whole wheat bread
B) granite
C) tap water
D) oil-water mixture

C) tap water

How well did you know this?

Not at all

Perfectly

A solution that contains a large concentration of solute but can hold even more solute is:
A) unsaturated and dilute
B) saturated and dilute
C) unsaturated and concentrated
D) saturated and concentrated

C) unsaturated and concentrated

How well did you know this?

Not at all

Perfectly

What is the main gas found in the air we breathe?

Nitrogen 78%

How well did you know this?

Not at all

Perfectly

Sodium sulphate is a:
A) homogeneous mixture
B) compound
C) heterogeneous mixture
D) mixture of elements

B) compound

How well did you know this?

Not at all

Perfectly

What does anhydrous mean?
A) a saturated solution
B) without water
C) contains a lot of water
D) an unsaturated solution

B) without water

How well did you know this?

Not at all

Perfectly

What does hygroscopic mean?
A) hydrophobic
B) insoluble in water
C) readily absorbs water
D) none of the previous answers

C) readily absorbs water

How well did you know this?

Not at all

Perfectly

What is the numerical value of Avogadro constant?
A) 1.66 x 10-27 kg
B) 22.41 dm3.mol-1
C) 6.023 x10 to the power 23 mol-1
D) 8.314 jk -1 mol-1

C) 6.023 x10 to the power 23 mol-1

How well did you know this?

Not at all

Perfectly

According to the modern periodic law, the chemical properties of the elements are periodic function of their:
A) atomic masses
B) atomic weights
C) atomic number
D) molar mass

C) atomic number

How well did you know this?

Not at all

Perfectly

The melting of ice is a:
A) chemical change
B) physical change
C) heterogeneous mixture
D) compound

B) physical change

How well did you know this?

Not at all

Perfectly

Vodka is a:
A) heterogeneous mixture
B) compound
C) element
D) homogeneous mixture

D) homogeneous mixture

How well did you know this?

Not at all

Perfectly

All elements in a a group 1 have the same:
A) number of electrons shells
B) mass number
C) atomic number
D) number of electrons in the outermost electron shell

D) number of electrons in the outermost electron shell

How well did you know this?

Not at all

Perfectly

Aqueous means:
A) it swims
B) without water
C) in water solution
D) none of the pervious answers

C) in water solution

How well did you know this?

Not at all

Perfectly

25. Vinegar and oil form: A) a homogeneous mixture B) a chemical change C) a compound D) none of the previous answers

D) none of the previous answers

26. Give the number of lone pair(s) in the molecule of nitrogen:

27. The element has a symbol X, give its group number _____ and period number ____

Group number - 15 Period number - 3

28. How many molecules are in one mole of CO?

6.022 x 10/23

29. The decomposition of hydrogen peroxide to water and oxygen is a: A) chemical change B) homogeneous mixture C) physical change D) Compound

A) chemical change

30. Orange juice is a: A) homogeneous mixture B) heterogeneous mixture C) unsaturated solution D) compound

B) heterogeneous mixture

31. Which of these processes is an example of a chemical change? A) methane is burned in air B) solid gold is melted to make jewellery C) a bar of copper is stretched into a long copper wire D) iron is coated with bronze to prevent rusting

A) methane is burned in air

32. 1ųmol is: A) 10-3 mol B) 10-6 mol C) 10-9 mol D) 10 6 mol

B) 10-6 mol

33. Which of these possibilities is an example of a homogeneous mixture? A) a bowl of noodle soup B) a container of water and sand C) a glass of salt water D) a bottle of oil and vinegar

C) a glass of salt water

34. This halogen is the only liquid non-metal at room temperature: A) Br B) Bi C) B D) Ba

A) Br

35. Which of these is not a solution? A) blood B) salt water C) water D) urine

C) water

36. An unsaturated salt solution is a: A) heterogeneous mixture B) homogeneous mixture C) physical change D) compound

B) homogeneous mixture

37. Express the following quantity in grams: 595.5 mg

0.5955g

38. The solvent in a vinegar is: A) wine B) water C) acetic acid D) salt

B) water

39. A dissolved solute that does not form ions is: A) nonelectrolyte B) weak electrolyte C) strong electrolyte D) insoluble

A) nonelectrolyte

40. The substance that is the result of a chemical reaction is called a: A) reactant B) product C) catalyst D) inhibitor

B) product

41. Which process represents a chemical change? A) oxidation B) sublimation C) evaporation D) condensation

A) oxidation

42. Evaporation of mercury is: A) mercury does not evaporate B) a chemical change C) a heterogeneous mixture D) a physical change

D) a physical change

43. A homogeneous mixture of two or more substances is a: A) solution B) solute C) solvent D) suspension

A) solution

44. The substance present in a smaller amount in a homogeneous mixture is a: A) solution B) solute C) solvent D) catalyst

B) solute

45. The substance present in a larger amount in a homogeneous mixture is: A) solution B) solute C) solvent D) catalyst

C) solvent

46. Which of the following is not a noble gas? A) hydrogen B) helium C) argon D) neon

A) hydrogen

47. What kind of element do you find on the far left-hand side of the periodic table? A) a metal B) a halogen C) a gas D) a negative ion

A) a metal

48. What are the most common elements in the human body? A) phosphorus, nitrogen, calcium B) sulphur, sodium, magnesium a C) copper, zinc, selenium D) oxygen, carbon and hydrogen

D) oxygen, carbon and hydrogen

49. Which element can be found in nature in a free (uncombined) state? A) Au B) Al C) Ca D) Ba

A) Au

50. All of the following elements are liquids at room temperature except: A) gallium B) magnesium C) bromine D) mercury

B) magnesium

51. A liquid has: A) a defined volume, but not a defined shape B) a definite shape, but no defined volume C) a definite volume and shape D) no defined volume or shape

A) a defined volume, but not a defined shape

52. Choose the chemical element which has similar name in English and Latin: A) Ag B) Ni C) K D) Fe

B) Ni

53. Choose the chemical element which has absolutely different name in English and Latin: A) Pb B) Al C) B D) P

A) Pb

54. Choose the physical process: A) the mixing of flour with sugar B) the mixing of sodium with water C) the burning of magnesium in CO2 D) the rusting of iron

A) the mixing of flour with sugar

55. Choose a compound: A) pyrite B) gold C) silver D) bronze

A) pyrite

56. Based on their positions in the periodic table, choose the atom in the following pair that have the greater metallic character: Li, Be

57. The electron configuration notation for the element of atomic number 5 is: A) 1s2 2p3 B) 1s5 C) 1s2 2s2 2p1 D) 1s2 2s1 2p2

C) 1s2 2s2 2p1

58. Write next to the following set of quantum numbers whether it is permissible or not (yes or no) : n=1 l=0 m=-1

59. The atomic number of an element is equal to: A) the number of neutrons in the atom B) the number of protons plus the number of neutrons C) the number of electrons in the atom D) the number of protons plus the number of electrons

C) the number of electrons in the atom

60. How many valence electrons are in the atom of sulphur 16S? A) 2 B) 4 C) 6 D) 1

C) 6

61. How many electrons are present in an atom of calcium that has the electron configuration 1s2 2s2 2p6 3s2 3p6 4s2? A) 6 B) 16 C) 20 D) 36

C) 20

62. Which of the following terms does describe an ion the best? A) an isotope B) an organic compound C) a chemical bond D) a charged molecule

D) a charged molecule

63. How many electrons are in the 2d subshell? A) 2 B) 6 C) 0 D) 10

C) 0

64. The general election configuration for all elements in group 15 (VA) is : A) ns2 np6 B) ns2 np5 C) ns2 np3 D) ns2 np3

D) ns2 np3

65. Which of the following particle has a positive charge? A) proton B) neutron C) anion D) electron

A) proton

66. The atom has atomic number 17 and a mass number 37. How many neutrons does the atom contain? A) 17 B) 20 C) 37 D) 54

B) 20

67. What is the electron configuration of a sodium ion? A) 1s2 2s2 2p6 3s1 B) 1s2 2s2 2p6 C) 1s2 2s2 2p6 3s2 D) 1s2 2s2 2p5 3s1

A) 1s2 2s2 2p6 3s1

68. The atom has Z = 27 and A = 60. How many protons and electrons are in this atom?

Protons: 27 Electrons: 27

69. Atomic radii of chemical elements in A subgroups increase from: A) left to right/ bottom to top B) right to left/ top to bottom C) left to right/ top to bottom D) right to left/ bottom to top

B) right to left/ top to bottom

70. An atom or group of atoms that have a net positive or negative charge is a: A) isotope B) radical C) orbital D) ion

D) ion

71. What is the maximal number of electrons in an atom that have the following quantum numbers: n = 5 l = 3

72. A horizontal row of elements in the periodic table is known as a: A) period or series B) group or family C) atomic number D) size

A) period or series

73. The momentum quantum number (l) of an orbital indicates the _____ of the orbital.

Shape

74. Write next to the following set of quantum numbers whether it is permissible or not (yes or no): n=2 l=1 m=1

Yes

75. An element with electron configuration 1s2 2s2 2p6 3s2 3p6 4s1 belongs to the: A) halogen gas group B) noble gas group C) alkaline earth metal group D) alkali metal group

D) alkali metal group

76. Identify the group in which all elements have the valence shell configuration ns2: A) group IA B) group IIA C) group IB D) group IIB

B) group IIA

77. An electron has the following set of quantum numbers: n=4 l=1 m=0 and s=+1/2. In which of the following orbitals would this electron be found? A) 4s B) 4px C) 4dxy D) 4f

B) 4px

78. The elements of the noble gas family, except for helium, have an outer shell of ___ electrons.

79. Which of the following compounds does not contain ions? A) molten sodium chloride B) glucose C) hydrochloric acid D) solid potassium chloride

B) glucose

80. Is the following set of quantum numbers permissible or not? (write yes or no) n=2 l=0 m=1

81. The maximum number of orbitals in the third shell is: A) 2 B) 4 C) 9 D) 16

C) 9

82. The energy required to remove an electron from an atom is known as: A) electronegativity B) ionisation energy C) electron affinity D) radioactivity

B) ionisation energy

83. Indicate the numbers of protons, neutrons and electrons in 109 Ag 47:

47 protons, 47 electrons and 62 neutrons

84. An orbital that would never exist in the quantum description of an atom is: A) 3d B) 2p C) 6d D) 3f

D) 3f

85. What is the electron configuration of S2- ?

1s2 2s2 2p6 3s2 3p6

86. Which of the following quantum numbers describes a “p” orbital in the third energy level? A) n=3 l=0 m=0 B) n=3 l=1 m=0 C) n=3 l=-1 m=0 D) n=4 l=3 m=0

B) n=3 l=1 m=0

87. Is the following set of quantum numbers permissible or not? n=2 l=1 m=0

Yes

88. Which of the following does the angular momentum quantum number indicate? A) the shape of an orbital B) the main energy level of an electron C) the orientation of an orbital around the nucleus D) the spin state of an electron in an orbital

A) the shape of an orbital

89. Assign oxidation numbers to N in the following compound: NH3

-3

90. Which is not true for the “p” orbitals? A) they are dumbbell shaped B) they are oriented about 3 axes C) they are found in all energy levels D) they may contain a total of 6 electrons

C) they are found in all energy levels

91. What is the name of the particle that has more protons that electrons? A) molecule B) isotope C) anion D) cation

D) cation

92. Which part of an atom is most directly involved in formation of chemical bond? A) nucleus B) electron C) proton D) neutron

B) electron

93. Electronegativity of chemical elements in A subgroups increases from: A) left to right/ bottom to top B) left to right/ top to bottom C) right to left/ top to bottom D) right to left/ bottom to top

A) left to right/ bottom to top

94. What is the electron configuration for 13 Al3+?

1s2 2s2 2p6

95. How many neutrons are there in an atom of lead with mass number 208 and atomic number 82? A) 82 B) 126 C) 208 D) 290

B) 126

96. Choose the larger atom in the pair: P or Sb

97. The number of “p” orbitals in each energy level above the first is: A) 1 B) 3 C) 4 D) 5

B) 3

98. How many orbitals are in the subshell 3d?

99. The mass number of an atom is determined by: A) the number of protons only B) adding the protons and electrons C) adding the neutrons and protons D) adding the neutrons and electrons

C) adding the neutrons and protons

100. How many electrons are in the 3d subshell?

101. Which of the following symbols represents impossible orbital? A) 1p B) 3p C) 4f D) 7s

A) 1p

102. Cations have a ____ charge and are ____ than the atoms of which they are formed: A) positive/ smaller B) negative/ smaller C) negative/ larger D) positive/ larger

A) positive/ smaller

103. Is the following set of quantum numbers allowed? n=3 l=2 m=3 s=-1/2

104. The principal quantum number of an orbital is 4. What are the possible angular momentum qantum numbers? A) 1/2, -1/2 B) -3, -2, -1, 0, 1, 2, 3 C) 0, 1, 2, 3 D) 4

C) 0, 1, 2, 3

105. Which one is larger in size, S or S2- ?

S2-

106. The maximum number of electrons at n=2 is: A) 32 B) 4 C) 8 D) 18

C) 8

107. Assign oxidation numbers to N in the following compound: N2 (N squared)

108. Determine the oxidation number for sulphur in the following substance: SO3

109. How many electrons are present in an atom where the 1s, 2s, and 2p subshells are filled? A) 10 B) 6 C) 7 D) 3

A) 10

110. What is the maximum number of electrons in the 2p subshell of an atom?

111. Choose the most electronegative atom among the following: S, Se, Cl, Br

112. “No two electrons in the same atom can have the same four quantum numbers” - it is a statement of: A) Bohr’s Law B) Hund’s rule C) the Aufbau principle D) The Pauli exclusion principle

D) the Pauli exclusion principle

113. What is the maximal number of electrons in an atom that have the following quantum numbers: n=2 s=-1/2

114. The noble-gas notation for the electron configuration of bromine is [Ar] 3d10 4s2 4p5. How many unpaired electrons are there in an atom of bromine in the ground state? A) 0 B) 1 C) 3 D) 5

B) 1

115. Arrange the following atoms in order of increasing atomic radius: F, P, S, As

F < S < P < As

116. What is the numerical value of atomic mass unit? A) 22.41 dm3.mol-1 B) 8.314 JK-1 mol-1 C) 6.023. 1023 mol-1 D) 1.66x10-27 kg

D) 1.66x10-27 kg

117. How many protons and electrons does the sodium ion have?

11 P 10 E

118. What is the valence of S in sulphur trioxide? A) II B) III D) IV D) VI

D) VI

119. Metallic properties of chemical elements in A subgroups increase from: A) left to right/ top to bottom B) right to left/ top to bottom C) left to right/ bottom to top D) right to left/ bottom to top

B) right to left/ top to bottom

120. Chemical bonds may be produced by any of the following processes involving electrons except: A) gaining electrons B) splitting electrons C) sharing electrons D) losing electrons

B) splitting electrons

121. Based on their position in the periodic table, choose the atom in the following pair that will have the larger first ionisation energy: O, Ne

122. A Bond that occurs between non metal and non metal is called a: A) covalent bond B) ionic bond C) hydrogen bond D) non metal bond

A) covalent bond

123. Which of the diatomic element has a double bond between its atoms? A) hydrogen B) nitrogen C) oxygen D) chlorine

C) oxygen

124. Write the usual valence associated with oxygen in covalent compounds:

-11

125. In hydrocarbons, the C and H atoms are joined together by: A) hydrogen bonds B) ionic bonds C) dipole-dipole attractions D) covalent bonds

D) covalent bonds

126. Ionization energy of chemical elements in A subgroups increases from: A) left to right/ top to bottom B) right to left/ top to bottom C) left to right/ bottom to top D) right to left/ bottom to top

C) left to right/ bottom to top

127. A bond between metal and non metal is generally: A) hydrogen B) metallic C) ionic D) covalent

C) ionic

128. In ionic bonds, valence electrons are: A) transferred B) destroyed C) unequally shared D) equally shared

A) transferred

129. What is the total number of sigma bonds found in the following compound? H3C - CH= C= CH- C(triple bond) CH

130. Bond between atoms of the metal is generally: A) ionic B) metallic C) coordinate D) hydrogen

B) metallic

131. What is the total number of pi bonds found in 1,3- butadiene?

132. Which of the diatomic elements has a triple bond between its atoms? A) Chlorine B) hydrogen C) oxygen D) nitrogen

D) nitrogen

133. What type of chemical bond holds the atoms together within a water molecule? A) ionic bond B) nonpolar covalent bond C) hydrogen bond D) polar covalent bond

D) polar covalent bond

134. How many covalent bonds are formed by each atom in the molecule of H20? A) 0 B) 1 C) 2 D) 3

C) 2

135. What force hold together oppositely charged ions in an ionic compound? A) electrostatic force B) contact force C) friction force D) hydrogen force

A) electrostatic force

136. An oxidation number of the metal in a molecule of Li2SO4 is: A) -II B) I C) VI D) II

B) I

137. Write the usual valence associated with nitrogen in covalent compounds:

111

138. Which of the following compounds contains a coordinate covalent bond: A) H2O B) NH3 C) H2O+ D) pbCl2

C) H2O+

139. Assign an oxidation number of a metal in the molecule CaSO4:

140. Name a force that keeps molecules together: A) friendship B) detraction C) attraction D) phlegmatic

C) attraction

141. What will be the formula of an ionic compound formed by calcium and oxygen? A) Ca2O B) CaO2 C) CaO3 D) CaO

D) CaO

142. Oxygen is in group 16 of the periodic table. How many covalent bonds does it usually form? A) 6 B) 2 C) 8 D) 4

B) 2

143. Positively charged ion is formed by an atom: A) gaining an electron B) losing an electron C) gaining a proton D) losing a proton

B) losing an election

144. Is k2SO4 ionic or molecular compound?

Ionic

145. What is the term for a water molecule that gains an extra hydrogen ion? A) hydronium ion B) hydroxide ion C) hydroxium ion D) none of the above

A) hydronium ion

146. Which of the following formulas is correct for hydrosulphuric acid ? A) H2SO4 B) H2S C) H2SO3 D) SO42-

B) H2S

147. For which element stays the chemical symbol K?

Potassium

148. What is the correct name for an aqueous solution of HCIO4? A) Hypochlorous acid B) chlorous acid C) chloric acid D) perchloric acid

D) perchloric acid

149. Which of the following compounds is not a salt? A) BaCrO4 B) FeCl2 C) K2SO4 D) Mg(OH)2

D) Mg(OH)2

150. What is the chemical formula for sodium carbonate? A) NaCO3 B) Na(CO3)2 C) Na2CO3 D) Na3CO3

C) Na2CO3

151. Determine the oxidation number of metal in K2CO3

152. Select the correct name for NH3: A) ammonium B) ammonium hydroxide C) pneumonia D) ammonia

D) ammonia

153. Magnesium atoms loose two electrons when they react. The symbol for the resulting ion is: A) Mg2- B) Mg2 C) Mg2+ D) Mg22+

C) Mg2+

154. Write the formula for copper(II) oxide:

C40

155. Which of the following formulas is the correct one for barium sulphide? A) BaS2 B) Ba2S C) BaS D) BaSO3

C] BaS

156. Select the correct formula for calcium nitrate: A) CaNO3 B) Ca(NO3)2 C) Ca(NO2)2 D) Ca2(NO3)3

B) Ca(NO3)2

157. Name the following compound Co(NO3)3:

Colbalt (III) Nitrate

158. What is the correct name for the ion NH4+? A) ammonium B) ammonia C) nitrate D) nitrogen tetrahydride

A) ammonium

159. Which name/ formula combination is correct? A) magnesium nitrate/ MgNO3 B) barium hypochlorite/ Ba(CIO)2 C) cadmium permanganate/ CdMnO4 D) Ammonium sulphide/ NH4S

B) barium hypochlorite/ Ba(CIO)2

160. What is the correct name for the ion SO4 2-? A) sulphur tetroxide B) sulphate C) sulphide D) Sulphite

B) sulphate

161. Identify the table salt: A) NaHCO3 B) KCl C) KOH D) NaCl

D) NaCl

162. Chloride, sulphate, nitrate are: A) anions B) cations C) elements D) compounds

A) anions

163. Give the corresponding name to the symbol Pd:

Lead

164. Potassium atoms loose one electron when they react. Write the symbol of the resulting

K+

165. What is the correct name of the ion CO3 2- ? A) carbonite B) oxalate C) bicarbonate D) carbonate

D) carbonate

166. What is the name of the compound NaCl? A) hydrogen bromide B) potassium chloride C) sodium dichloride D) sodium chloride

D) sodium chloride

167. Noble gases are inert because they have completed outer electron shells. Which of these elements isn’t a Noble gas? A) helium B) argon C) chlorine D) krypton

C) chlorine

168. What is chemical formula of water? A) H2 B) O2 C) H2O D) H202

C) H20

169. Who is credited with the invention of the modern periodic table? A) Nobel B) Lavoisier C) Mendel D) Mendeleev

D) Mendeleev

170. Which of these elements is a nonmetal? A) sulphur B) manganese C) aluminum D) beryllium

A) sulphur

171. Name the compound ZnSO3

Zinc Sulphate

172. What is the chemical formula of calcium carbonate?

CaCo3

173. What is the name of the compound K2SO4?

Potassium suphate

174. Give the name of the element with the following atomic symbol: Hg

Mercury

175. Give the name of the element with the following atomic symbol: P

Phosphorus

176. Give the name of the element with the following atomic symbol: F

Fluorine

177. What is the chemical formula of magnesium phosphate?

Mg3(PO4)2

178. What is the name of the compound KCIO4?

Potassium Perchlorate

179. Write the name of the element next to the atomic symbol: Ar

Argon

180. Write the name of the element next to the atomic symbol: Cu

Copper

181. Write the molecular formula next to the name of the following compound: sodium nitrate

NaNO2

182. The chemical equation shows the production of calcium oxide and carbon dioxide: CaCO3 ——> CaO + CO2 The reaction should be classified as: A) decomposition B) composition C) single replacement D) double replacement

A) decomposition

183. Neutralisation is the chemical process in which: A) sodium ions react with chloride ions to form sodium chloride B) hydrogen ions react with hydroxide ions to form water C) sodium ions react with hydroxide ions to form sodium hydroxide D) hydrogen ions react with chloride ions to form hydrogen chloride

B) hydrogen ions react with hydroxide ions to form water

184. What is true in regard to single-displacement reactions? A) only one product is formed B) there is only one reagent C) it requires oxygen D) one element replaces another in a compound

D) one element replaces another in a compound

185. Identify the salt in the following reaction: KOH(an) + HBr(aq) —-> H20(l) + KBr(aq) A) KOH B) HBr C) H20 D) KBr

D) KBr

186. In the reaction described by the equation Na+H2O —-> NaOH+H2 A) sodium hydroxide is a reactant B) sodium is a product C) water is a product D) hydrogen gas is a product

D) hydrogen is a product

187. What name is given to the substance that are initially involved in chemical reaction?

Reactants

188. What are the products of the decomposition of mercury(II) oxide? A) Hg2 and O2 B) Hg2 and O C) Hg and O2 D) HgO and O2

C) Hg and O2

189. Which equation below violates the law of conservation of mass ? A) 2 H2+ O2 —> 2 H2O B) KCL + Br2 —> KBr + Cl2 C) 2 Fe2O3 + 3C —> 4 Fe + 3 CO2 D) Na2 CO3 + 2HCL —> 2 NaCl+ H2O + CO2

C) 2 Fe2O3 + 3C —> 4 Fe + 3 CO2

190. Which coefficients correctly balance the formula equation below? KCIO3(s) —> KCI(s) + O2(g) A) 1, 1, 1 B) 1, 1, 3 C) 2, 2, 3 D) 2, 1, 1

C) 2, 2, 3

191. Which two substances are always produced by a neutralization reaction? a) water and an acid b) water and a salt c) water and a base d) an acid and a base

B) water and a salt

192. Which of the following formulations indicate that the chemical equation is balanced? a) the numbers of atoms of each element are the same on both sides of the equation b) all of the coefficients are the same c) thenumbersofmoleculesoneachsideoftheequationareequal d) the sums of the coefficients on each side of the equation are equal

a) the numbers of atoms of each element are the same on both sides of the equation

193. In a reaction, the ions of two compounds exchange places in aqueous solution to form two new compounds. This reaction is called a: a) synthesisreaction b) decomposition reaction c) single-displacementreaction d) double-displacement reaction

d) double-displacement reaction

194. The formation of a solid product in a chemical reaction is represented by the symbol: a) (aq) b) (g) c) (/) d) (s)

D) (s)

195. Write the balanced equation for the following acid-base reaction: 2 H C I 0 4 + _ C a ( O H ) 2 ➔

H 2 O + C a ( C l O 4 ) 2

196. How many moles of carbon monoxide are needed to react completely with seven moles of oxygen gas to form carbon dioxide? 2 CO(g) + 02(g) ➔ 2 C02(g) a) 3.5 b) 7 c) 21 d) 14

D) 14

197. The substance that enters a chemical reaction is called a(n): a) reactant b) product c) catalyst d) inhibitor

A) reactant

198. The neutralization of any strong acid and strong base produces mostly: a) H20 molecules b) H30+ and OH- ions c) H3O+ ions d) 0H- ions

a) H20 molecules

199. What salt is formed in the following acid/base reaction? HCI03 + Ba(OH)2 -> a) BaCl2 b) BaC103 c) H20 d) Ba(CI03)2 •

d) Ba(CI03)2

200. Identify the redox reaction: a) Mg+2HCI-->MgC12+H2 b) KOH+HNO3->KNO3+H20 c) Pb(NO3)2+2HBr->PbBr2+2HNO3 d) Ca(OH)2+2HCI->2H20+CaCl2

a) Mg+2HCI-->MgC12+H2

201. Write the balanced equation for the following acid-base reaction —H2SO3 + —Ni(OH)3 —> ______________

3 2 Ni2(SO3)3+6H2O

202. Write the balanced equation for the following reaction: __KOH + __CO2 —-> ___K2CO3 +__ H20

2 ? ? ?

203. Write the balanced equation for the following reaction: __Na + __Cl2 —> __ NaCl

2 ? 2

204. Oxidation means: a) losing electrons and increasing of oxidation number b) gaining electrons and decreasing of oxidation number c) losing electrons and decreasing of oxidation number d) gaining electrons and increasing of oxidation number

a) losing electrons and increasing of oxidation number

205. Balance the following chemical equation: __Al4C3+ __H20 —-> __Al(OH)3 +__CH4

? 12 4 3

206. Write a balanced chemical equation that represents the decomposition of solid ammonium nitrate into dinitrogen monoxide gas and liquid water, indicate the states of the reactants and products:

207. Write a balanced equation for reaction of iron(III) oxide with carbon monoxide to give iron metal and carbon dioxide:

208. Write a balanced equation for the following reaction written in words: potassium dissolves in water to give potassium hydroxide and hydrogen gas

209. Classify the following reaction as a precipitation, an oxidation-reduction, or an acid-base reaction: KCI(aq) + AgNO3(aq) -> KNO3(aq) + AgCl(s)

Precipitation

210. Write a balanced chemical equation for the neutralization of barium hydroxide by hydrochloric acid:

211. What is the pH of a solution with p0H = 10.0?

pH = 4

212. What is the mass percentage of sulphur in ammonium sulphate? Mm(S) = 32 g•mol-1 Mm((NH4)2SO4) = 132 g.mol-1 a) 6.7% b) 24% c) 28% d) 32%

B) 24%

213. 250 g of 50% HNO3 were diluted with 150 g of water. Calculate the mass percentage of diluted acid.

W= 31.25%

214. What would be the mass percentage of a solution made by mixing of 150 g of 10 % HCl and 100 g of 25 % HCI?

W=16%

215. When a solution has a pH of 4, what is the p0H of that solution? a) 7 b) 18 c) 10 d) 4

C)10

216. How many nitrogen atoms are in 28 g of nitrogen molecule? Ar(N) = 14

217. How many atoms are in 3.50 mol of calcium? a) 4.00.101 b) 1.40.102 c) 6.02.1023 d) 2.10.1024

d) 2.10.1024

218. What is the molar concentration of a 100.00 mL aqueous solution that contains 1.00 g KCI? Mm(KCI) = 74.55 g.mol-1 a) 1.34mol.dm-3 b) 0.134 mol.dm-3 c) 0.0134 mol.dm-3 d) 0.00134 mol.dm-3

b) 0.134 mol.dm-3

219. To determine molarity of a HCI solution, you need to know the number of: a) grams of HCI in 1 106g of solution b) moles of HCI dissolved in the total moles of solution c) moles of HCI in 1L of solution d) moles of HCI dissolved in 1 kg of solvent

c) moles of HCI in 1L of solution

220. What is the approximate mass of 1.50 mol of ammonia? Mm(NH3) = 17 g•mol-1 a) 10.0g b) 15.0g c) 17.0g d) 25.5 g

D) 25.5g

221. What is the mass in grams of 150.1012 iron atoms when each have the atomic mass of 56 u?

222. What is the molar concentration of a solution that contains 0.202 mol KCl in 7.98 L of solution? Mm(KCI) = 74.55 g•mol-1 a) 0.0132 mol.dm- 3 b) 0.0253 mol.dm-3 c) 0.459 mol.dm-3 d) 1.36 mol•dm-3

b) 0.0253 mol.dm-3

223. How many mL of 60% acetic acid with density p = 1.0629 g.cm-3 you need to prepare 250 mL 0.02 mol.dm-3 solution. Mm(CH3COOH)= 60 g.mol-1

0.47ml

224. How many grams of water can be prepared from 8 grams e temperature and pressure? Mm(H20) = 18 g•mol-1 Mm(H2) = 2g•mol-1 a) 18 b) 8 c) 72 d) 2

C) 72

225. What is the molar concentration of a solution made by dissolving 5g of FeSO4 in water diluted to a final volume of 500 mL? Mm(FeSO4) = 152 g•mol-1

226. When 20ml of 1mol.dm-3 HCl is added to 10ml of 1 mol.dm-3 NaOH the the resulting solution is: a) red b) acidic c) neutral d) basic

B) acidic

227. How many moles of oxygen are required to burn 22.4 litres of ethane gas at standard temperature and pressure? 2 C2H6(g) + 702(g) —> 4CO2(g)+6H2O(g) a) 11.2 b) 7 c) 3.5 d) 14

C) 3.5

228. How many grams of sodium chloride are approximately required to prepare 500 mL of a 3.00 mol•dm-3 solution? Mm(NaCl) = 58.44 g•mol-1 a) 39.0g b) 58.4g c) 87.7g d) 167g

C) 87.7g

229. Express the following quantity in litres: 15 mL

0.0015L

230. The concentration of H* in solution is 1.10-4 mol•dm-3. pH of the solution is: a) 10 b) 14 c) 4 d) 1.10-10

C) 4

231. 80 g of NaOH is dissolved in 2000 ml of solution. Calculate the molar concentration of solution. Mm(NaOH) = 40 g•mol-1 a) 40mol•dm-3 b) 82 mol•dm-3 c) 160mo1-dm-3 d) 1 mol.dm-3

d) 1 mol.dm-3

232. How many grams of KCl are needed to prepare 400 g of a 2.5% saline solution?

10g

233. How many grams of NaCI are needed to prepare 250 ml of a 1.5% saline solution? p(1.5 %) = 1.012 g/cm3

3.795g

234. Calculate the p0H of 0.01 mol•dm-3 HNO3 solution

pOH=12

235. When 10 ml of 1 mol•dm-3 HCI is added to 10 ml of 1 mol•dm-3 NaOH, the resulting solution is: a) basic b) acidic c) neutral d) coloured

C) neutral

236. If pH of solution of NaOH is 12.0, the pH of HCI solution of same molarity is: a) 2.0 b) 12.0 c) 1.7 d) 10.0387

A) 2

237. Determine the percentage composition of the lithium chloride monohydrate. Ar(Li) = 6.941 Ar(CI) = 35.45 Ar(H) = 1.008 Ar(0) = 16.00

Li: 11.49% Cl: 58.68% H: 3.337% O: 26.49%

238. What is the mass of one mole of methanol? Ar(C) = 12.01 Ar(H) = 1.008 Ar(0) = 16.00

32.04g

239. What is the molar mass of K2SO4? Ar(K) = 39.10 Ar(S) = 32.07 Ar(0) = 16.00

174.27 g/mol

240. The equation for preparing chlorine gas from HCI is: 4 HCI(g) + 02(g) —-> 2 Cl2(g) + 2 H20(g) How many kilograms of HCI are required to produce 1750 kg of Cl2?

1800kg

241. What is the volume in litres of 10.00 g of oxygen gas at standard temperature and pressure? Mm(O2) = 32.00g/mol

7.00L

242. What is the molar mass of PbCO3? A(Pb) = 207.2 Ar(C) = 12.01 Ar(0) = 16.00

267.2g/mol

243. How many stages of ionization does phosphoric acid go through? a) one b) two c) three d) four

244. Acids have a pH value that is: a) lower than 7 b) higher than 7 c) equal to 7 d) between 9 and 14

245. Bases have a pH value below 7. a) true b) false

246. According to the Bronsted-Lowry theory, an acid is a: a) proton acceptor b) proton c) proton donor d) proton destroyer

247. Acids have a pH value below 7. a) true b) false

248. A strong base in an aqueous solution: a) is a weak electrolyte b) produces many H+ ions c) will not dissolve d) completely dissociates into ions

249. Which of the following compounds is a base? a) LiOH b) BaCl2 c) KI d) KNO3

250. Which of the following solutions is the most basic? a) pH=12.0 b) p0H=12.0 c) pH=3.0 d) p0H=3.0

251. Which of the following is a Bronsted-Lowry base? a) HCI b) HCO3- c) H30+ d) H3PO4

252. Is sodium hydroxide an acid or a base?

Base

253. Write formula for the conjugative acid of HP042-:

H2PO4-

254. In a Bronsted-Lowry acid-base reaction, what is transferred from one reactant to another? a) electron b) water molecule c) H+ion d) OH- ion

255. Water solution of Fe504 is: a) acidic b) basic c) neutral d) hot

256. When acids are dissolved in water they produce ions that help in conducting the electricity. This process is known as: a) galvanisation b) vulcanisation c) dissociation d) none of the above

257. What is the range of the pH scale from lowest to highest? a) 0 to 100 b) 0 to10 c) 0 to14 d) 0 to 7

258. In the reaction represented by the following equation, the conjugate acid-base pair is: H2C204(aq) + CH3NH2(aq) <===> HC204(aq)+ CH3NH3(aq) a) H2C204(aq)andCH3NH2(aq) b) H2C204(aq) and CH3NH3+(aq) c) CH3NH2(aq)andCH3NH3(aq) d) HC204-(aq) and CH3NH3 (aq)

259. Strong acids: a) ionize slightly and produce a few hydroxide ions in solution b) ionize completely and produce many hydroxide ions in solution c) ionize slightly and produce a few hydrogen ions in solution d) ionize completely and produce many hydrogen ions in solution

260. How many protons per molecule can a monoprotic acid donate? a) one b) two c) three d) zero

261. What is the numerical value of water ionic product?

262. Which one of the following could not be a Bronsted-Lowry acid? a) NH4. b) BF3 c) H30+ d) H2O

263. When HC104 ionizes in water, CI04- is the: a) acid b) conjugate base c) conjugate acid d) reactant

264. What value of the pH scale is considered to be for neutral liquid? a) 3 b) 7 c) 9 d) 14

265. According to the Bronsted-Lowry theory, a base is a: a) proton donor b) proton c) proton acceptor d) proton destroyer

266. A substance that increases the concentration of OH- ions in an aqueous solution is known as a(n): a) Arrhenius acid b) Arrhenius base c) Lewis acid d) Lewis base

267. The strongest bases are hydroxides of: a) halogens b) transition metals c) noblegases d) group 1 and group 2

268. Consider the following two equations. They illustrate that water is: H2SO4(aq) + H20(/) —> H30.+(aq) + HSO4 (aq) NH3(g) + H20(1) --> NH4+(aq) + OH-(aq) a) an acid in both reactions b) a base in both reactions c) amphiprotic d) a weak electrolyte

269. Which substance is a Lewis acid in the reaction shown by the following equation? BF3(aq) + F- (ag) <===> BF4-(aq) a) BF3 b) F- c) BF4- d) none of the above

270. Which of the following compounds is the conjugate base of H2SO4? a) H2S03 b) HSO4 c) HS- d) SO4 2-

271. Which acid is produced in the stomach? a) HNO3 b) CH3COOH c) H2S04 d) HCI

272. What is the conjugate acid of water? a) 0H- b) H30+ c) H202 d) HOH

273. HCI is a strong acid. When it combines with water, the conjugate pair to HCI will be a: a) weak base b) weak acid c) strong base d) strong acid

274. Water solution of Li2CO3 is: a) acidic b) basic c) neutral d) glacial

275. In the reaction represented by the following equation a conjugate acid-base pair is: HF(aq) + H20(/) <=, H30+(aq) + F-(aq) a) F-and H20 b) HF and F- c) H30+ and HF d) HF and H20

276. Which of following acid is not monoprotic? a) HCI b) HNO3 c) H2SO4 d) HCIO

277. Which of following bases is not monobasic? a) KOH b) NaOH c) Ba(OH)2 d) NH4OH

278. Arrhenius defined an acid as: a) a source of H+ ions in water b) a source of OH- ions in water c) a proton acceptor d) a proton donor

a) a source of H+ ions in water

279. Which of the following is classified as a conjugate acid-base pair? a) HCI / NaOH b) H30+ / H20 c) 02/H20 d) H+/ Cl-

b) H30+ / H20

280. Catalysts increase the rate of a chemical reaction by means of: a) increasing temperature b) lowering activation energy c) increasing the concentration of reactants d) increasing collision energy

b) lowering activation energy

281. Which of the following conditions will always increase the rate of a chemical reaction? a) an increase in pressure b) a decrease in pressure c) an increase in concentration of reactants d) an increase in temperature

c) an increase in concentration of reactants

282. A chemical reaction where the energy is released is called:

Exothermic

283. A chemical reaction in which the energy is absorbed is called:

Endothermic

284. What scientist is famous for his equilibrium principle? a) Arrhenius b) Bohr c) Lowry d) Le Chatelier

285. Express the equilibrium constant for the following reaction: 2 K(s) + 2 H20(l) <=> 2 KOH(aq) + H2(g)

286. A substance that is used to speed up a chemical reaction but is not used as a part of the reaction is called a(n): a) reactant b) product c) catalyst d) inhibitor

287. In the chemical reaction: 2 HCI(aq) + Mg(s) <=> MgCl2(aq) + H2(g) + heat a) energy is absorbed, so the reaction is endothermic b) energy is released, so the reaction is exothermic c) energy is released, so the reaction is endothermic d) energy is absorbed, so the reaction is exothermic

b) energy is released, so the reaction is exothermic

288. A reaction for which heat must be added to the system to maintain isothermal condition is called: a) endothermic reaction b) exothermic reaction c) neutral reaction d) homogeneous reaction

289. Temperature and pressure are the only factors affecting the reaction rate. a) true b) false

290. The frequency of molecular collision increases if: a) the concentration of products increases b) the concentration of products decreases c) the concentration of reactants increases d) the concentration of reactants decreases

291. What happens if you remove one of the products from a system at dynamic equilibrium? a) less products are made b) more products are made c) more reactants are made d) it has no effect

292. What is the effect of increasing the pressure on the following reaction? 2NO +O2 <=> 2 NO2 a) the yield of NO2 increases b) the yield of NO2 decreases c) the reaction is slower d) it has no effect

293. If the forward reaction is endothermic, what will be the effect of decreasing the temperature? a) increase the yield of the products b) decrease the yield of the products c) increase the reaction rate d) it has no effect