Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Animal Course Physiology Exam > 4.1 Atoms and Molecules > Flashcards

4.1 Atoms and Molecules Flashcards

1
Q
  1. The chemical formula C6H12O6 contains much information. However, what information is NOT provided by the formula?
    A. The number of atoms in a molecule
    B. The name of the substance
    C. The elements that make up the substance
    D. Whether the substance is covalent or ionic
A

Answer is B: The name may be guessed at, but it is possible for two substances to have the same formula but a different structure. Glucose and fructose both have this formula.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q
  1. Which of the particles listed below is the smallest?
    A. An atom
    B. A proton
    C. An ion
    D. A molecule
A

Answer is B: A proton is a subatomic particle so it is smaller than all of the others.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q
  1. The chemical symbol for sodium is which of the following?
    A. Na
    B. So
    C. K
    D. Si
A

Answer is A: Na is short for natrium which is the Latin name for sodium.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q
  1. A molecular compound may be defined by which of the following?
    A. Atoms from non-metal elements covalently bonded
    B. Atoms from metal elements covalently bonded
    C. Atoms from metal elements and non-metal elements covalently bonded
    D. Atoms from non-metal elements ironically bonded
A

Answer is A: Only non-metal elements are involved in covalent (molecular) bonding.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q
  1. Many drugs are neutralised to form salts and administered in this form. What is the main advantage of administering the salt form of the drug? It is usually:
    A. Less toxic
    B. More soluble in water
    C. More pleasant to taste
    D. More soluble in lipid
A

Answer is B: Salts, having particles that are electrically charged, are more likely to be soluble in water.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q
  1. One of the following is INCORRECT. Which one?
    A. Metal atoms will form compounds with non-metal atoms.
    B. Metal atoms will form compounds with metal atoms.
    C. Non-metal atoms will form compounds with non-metal atoms. D. Metal atoms will not form compounds with metal atoms.
A

Answer is B: Metal atoms can only form (ionic nonmolecular) compounds with non-metal atoms.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q
  1. Choose the correct statement about hydrogen bonds. They:
    A. Are stronger than covalent bonds
    B. Act between the H in one –OH or –NH group and the O or N in another
    C. Operate within molecules
    D. Act between the H in one –OH or –NH group and the H in another
A

Answer is B: The slightly positive H atom in one molecule is attracted to the adjacent slightly negative O (or N).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q
  1. Given that the atomic mass of nitrogen is 14 and that of hydrogen is 1, what is the mass in grams of 1 mole of ammonia (NH3)?
    A. 15
    B. 16
    C. 17
    D. 18
A

Answer is C: From the formula, there is one N and three H atoms. So (1×14) + (3×1) = 17.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q
  1. Choose the ending that will correctly complete the sentence: When atoms of a metal element and atoms of a non-metal element react, the result is:
    A. A covalent compound consisting of molecules
    B. A covalent compound consisting of ions
    C. An ionic compound consisting of ions in a lattice
    D. An ionic compound consisting of molecules in a lattice
A

Answer is C: Atoms of a metal element react with atoms of a non-metal element to form an ionic compound (ions held within a lattice when in solid form).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q
  1. In a water molecule, the bond between oxygen (O) and hydrogen (H) is:
    A. A covalent bond and a polar bond
    B. An ionic bond
    C. A covalent bond
    D. An ionic bond and forms an electrolyte
A

Answer is A: As both atoms are non-metals, the bonding is covalent. As the atoms differ in their attraction for the bonding electrons, the bond is polar (the electrons are more closely attracted to O).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q
  1. Some atoms of potassium, K, contain 19 protons and 20 neutrons in their nuclei. What is the correct symbol for these atoms?
    A. 20/ 19 K
    B. 19/ 20K
    C. 39/ 19K
    D. 20/ 39K
A

Answer is C: The number of protons (the atomic number) is written as a subscript. The sum of the number of protons and neutrons (the mass number) is written as a superscript.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q
  1. The chemical elements can be divided into metal elements and non-metal elements. Which of the statements about metals and non-metals is correct?
    A. Metals lose electrons to become charged particles called cations.
    B. Most of the elements are non-metals.
    C. Non-metals are located at the left-hand side of the periodic table.
    D. Metals have low melting points and are good conductors of heat.
A

Answer is A: Metal ions are positively charged (having lost an electron/s); consequently they are attracted to a cathode (a negatively charged electrode).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q
  1. Twenty-four of the chemical elements are essential to the human body. Four are bulk elements, 7 are macrominerals and 13 are trace elements. Which are the four bulk elements?
    A. Calcium, carbon, hydrogen and oxygen
    B. Nitrogen, carbon, hydrogen and oxygen
    C. Calcium, nitrogen, carbon and oxygen
    D. Carbon, oxygen, phosphorus and iron
A

Answer is B: These elements make up the bulk of proteins, carbohydrates and lipids.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q
  1. Most nonmolecular compounds form by the chemical combination of:
    A. Molecules with molecules
    B. Non-metals with non-metals
    C. Metals with metals
    D. Metals with non-metals
A

Answer is D: Ionic compounds are formed when metal atoms react with non-metal atoms. The structures that form are not molecular.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q
  1. Molecules are relatively easy to separate from one another. This means that the bonds between them are:
    A. Ionic
    B. Covalent
    C. Relatively weak
    D. Relatively strong
A

Answer is C: Ease of separation implies relatively weak bonds. Both ionic and covalent bonds are strong.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q
  1. What happens when a sodium atom reacts to form a compound? The atom will:
    A. Gain one electron
    B. Lose one electron
    C. Gain two electrons
    D. Lose two electrons
A

Answer is B: Sodium is a metal so it will lose an electron. As it occurs in Period IA of the periodic table, we know it loses a single electron.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q
  1. When nitrogen combines with hydrogen to form a compound, its formula will be:
    A. NH3
    B. N3H
    C. NH4
    D. NH
A

Answer is A: N requires three electrons to complete its outer shell (it occurs in column VA of the periodic table), while H requires one. Hence three H must attach to a single N.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q
  1. Which of the following type of bond between atoms is the weakest?
    A. Ionic bond
    B. Polar bond
    C. Covalent bond
    D. Hydrogen bond
A

Answer is D: The hydrogen bond is the weakest. Almost all covalent bonds are polar bonds.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q
  1. Ionic, nonmolecular compounds are likely to have which of the following sets of properties?
    A. High melting point, often soluble in organic liquids, in pure form do not conduct electricity
    B. Low melting point, no strong odour, soluble in water, electrical conductivity in solution
    C. High melting point, electrical conductivity in solution, no strong odour, often soluble in water
    D. Low melting point, strong odour, soluble in organic liquids, in pure form do not conduct electricity
A

Answer is C: High melting points and electrical conductivity are indicative of ionic compounds.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q
  1. Which of the following best describes a molecule?
    A. The simplest structure in an ionic compound
    B. One thousandth of a mole
    C. The particles of which covalent compounds are composed
    D. The smallest particle of an element
A

Answer is C: Molecules are the particles of covalent compounds.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q
  1. Which of the following is true of metal elements?
    A. The four most common metal elements in the body have the symbols C, H, O and N.
    B. They form compounds with non-metals.
    C. When they form compounds, they gain electrons.
    D. In the body, ions of metal atoms have a negative charge.
A

Answer is B: All other choices are wrong.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q
  1. Which of the following symbols represents a chemical element?
    A. O
    B. CO
    C. CO2
    D. H3O+
A

Answer is A: O symbolises oxygen, element number 16.

23
Q
  1. What is the name given to the particles that make up a covalent compound?
    A. Ions
    B. Molecules
    C. Anions and cations
    D. Metal atoms
A

Answer is B: This is a definition of molecules.

24
Q
  1. Compounds may be described by which of the following sentences?
    A. Pure substances that contain two or more elements
    B. Materials that are composed of particles called molecules
    C. Materials composed of more than one part, and the parts may be present in any proportion
    D. Substances that appear on the right-hand side of the periodic table
A

Answer is A: Choice B refers only to covalent compounds.

25
Q
  1. The symbol for potassium is which of the following?
    A. PO4
    B. Po
    C. P
    D. K
A

Answer is B: K is from kalium which is the Latin word for potassium.

26
Q
  1. “Covalent” is the term applied to which of the following bonds?
    A. Those between an ion and all the surrounding oppositely charged ions
    B. The bond between an electrolyte and the surrounding water molecules in a solution
    C. Those between non-metal atoms
    D. Those between atoms on the left-hand side of the periodic table
A

Answer is C: Non-metals share electrons when they react with each other (rather than losing or gaining), hence the prefix “co-”.

27
Q
  1. Given that 1 mol is 6 × 10^23 particles, how much is a millimole?
    A. 6×10^20 particles
    B. 10^6 mol
    C. 10^−6 mol
    D. 6×10^−3 particles
A

Answer is A: A millimole is one thousandth of a mole, so 1 mmol = 10−3 × 6 × 1023 =6×1020 particles.

28
Q
  1. Which of the following is a definition of a molecule? The particle that composes:
    A. Covalent compounds
    B. Non-metal elements
    C. Electrolytes
    D. Ionic compounds
A

Answer is A: This is one definition of a molecule.

29
Q
  1. What is the smallest particle of a non-metal element known as?
    A. A molecule
    B. An atom
    C. An ion
    D. A neutron
A

Answer is B: An atom is the smallest particle of any element – not just non-metals!

30
Q
  1. What is the difference between ions and molecules?
    A. Ions have an electrical charge, whereas molecules do not.
    B. Ions are from metal elements only, whereas molecules contain only non-metal elements.
    C. Ions arise from compounds between non-metal elements, whereas molecules arise from metal and non-metal elements.
    D. An ion may be formed from a single atom, but molecules always involve more than one atom.
A

Answer is D: This is the only correct choice. However molecules may also form ions – polyatomic ions.

31
Q
  1. Of the four different types of matter listed below, which is not an example of an element?
    A. Hydrogen
    B. Oxygen
    C. Water
    D. Gold
A

Answer is C: Water is a compound of H and O.

32
Q
  1. A certain pure substance, A, when heated is changed into two quite different pure substances, C and D. Which of the following statements must be true?
    A. A is a compound.
    B. C and D are not elements.
    C. A, C and D are all compounds.
    D. C and D are elements.
A

Answer is A: Only this choice must be true. The others are just possible.

33
Q
  1. Which of the following statements about atoms is FALSE?
    A. They are mostly empty space.
    B. Nearly all their mass is concentrated in the nucleus.
    C. In a neutral atom, protons and electrons are equal in number.
    D. The nucleus contains equal numbers of protons and neutrons.
A

Answer is D: For the elements with smaller atoms, usually this is true. For heavier elements it is not.

34
Q
  1. In which of the following sequences are particles listed in order of increasing size from left to right?
    A. Electron, atom, proton, molecule
    B. Molecule, atom, proton, electron
    C. Atom, proton, electron, molecule
    D. Electron, proton, atom, molecule
A

Answer is D: An electron so far is immeasurably small, while a molecule must have at least two atoms, and the proton is a subatomic particle.

35
Q
  1. Which of the following is the name of a subatomic particle?
    A. Anion
    B. Cation
    C. Molecule
    D. Neutron
A

Answer is D: A neutron is one of the constituents of the atomic nucleus.

36
Q
  1. Two atoms have the same mass number but different atomic numbers. Which of the following statements concerning these atoms is TRUE?
    A. Each has the same number of neutrons in its nucleus.
    B. They are isotopes.
    C. They are atoms of different elements.
    D. Each has the same number of protons in its nucleus.
A

Answer is C: Different atomic numbers means different numbers of protons and hence different elements.

37
Q
  1. What is the atomic number of the element occupying Group VA and Period IV of the periodic table?
    A. 33
    B. 34
    C. 51
    D. 52
A

Answer is A: This is arsenic (As) – you need to consult a periodic table to answer this.

38
Q
  1. Some atoms of iodine, I, contain 53 protons and 78 neutrons in their nuclei. A correct symbol for these atoms would be:
    A. 131/53 I
    B. 78/53 I
    C. 131/78 I
    D. 53/78 I
A

Answer is A: The convention is that the number of protons is the subscript and the sum of the number of protons and neutrons (131) is the superscript.

39
Q

Which of the following atoms normally forms ions having a single, positive charge?
A. Mg
B. S
C. Cl
D. K

A

Answer is D: This is because potassium is a metal and from group IA of the periodic table.

40
Q
  1. Which of the following statements concerning isotopes is FALSE?
    A. They contain the same number of protons in their atoms.
    B. They contain the same number of electrons in their atoms.
    C. They contain the same number of neutrons in their atoms.
    D. They have very similar chemical properties.
A

Answer is C: Having a different number of neutrons (while having the same number of protons) is what defines them to be isotopes

41
Q
  1. The element nitrogen exists as molecules, N2. Which of the following representations of the bonding in a molecule of nitrogen is correct?
    A. N+ N−
    B. N–N
    C. N=N
    D. N≡N
A

Answer is D: Nitrogen is placed in Period VA of the periodic table and so needs to share three electrons. That is, it needs to form three covalent bonds.

42
Q
  1. Which of the following properties is least likely to be possessed by a covalent, molecular substance?
    A. Strong odour
    B. High solubility in water
    C. Melting point above 400 °C
    D. Low electrical conductivity
A

Answer is C: A high melting point is characteristic of ionic substances. Some covalent compounds are soluble in water.

43
Q
  1. The diagrams below display the covalent bonds present in a series of simple molecules. In which case is the number of bonds surrounding an atom in the diagrams below INCORRECT?
    A. Carbon dioxide

O – C – O

B. Carbon tetrachloride

   CI CI - C - CI 
   CI

C. Ammonia

H - N - H
H

D. Water

H – O – H

A

Answer is A: Carbon must form four bonds (not two). It is from group IV A in the periodic table.

44
Q
  1. The formula for glucose is C6H12O6. How many atoms of each type of element are there in a molecule of glucose?
    A. 6 atoms of calcium, 12 atoms of helium and 6 atoms of osmium
    B. 1 atom of carbon, 6 atoms of hydrogen and 12 atoms of oxygen
    C. 1 atom of carbon, 18 atoms of hydrogen and 6 atoms of oxygen
    D. 6 atoms of carbon, 12 atoms of hydrogen and 6 atoms of oxygen
A

Answer is D: The number of atoms, written as a subscript, immediately follows the symbol for the element and C, H, O are the symbols for carbon, hydrogen and oxygen, respectively.

45
Q
  1. The formula for oleic acid (a fatty acid) may be written as: CH3(CH2)7CH=CH(CH2)7CO2H. How many atoms of each type of element are there in a molecule of oleic acid?
    *No numbers preceding atoms/ molecules
    A. 18 atoms of carbon, 11 atoms of hydrogen and 1 atom of oxygen
    B. 12 atoms of carbon, 10 atoms of hydrogen and 2 atoms of oxygen
    C. 18 atoms of carbon, 34 atoms of hydrogen and 2 atoms of oxygen
    D. 20 atoms of carbon, 23 atoms of hydrogen and 1 atom of oxygen
A

Answer is C: The number of atoms written as a subscript immediately follows the symbol for the element; hence there are 2 atoms of oxygen (O). The number 7 out- side the parentheses means that there are 7 lots of the atoms that are inside the parentheses. Hence, it is 14 + 14 H inside the parentheses, with a further 6 H outside them, which totals 34 H.

46
Q
  1. The formula for leucine (an amino acid) may be written as (CH3)2C3H4NH2COOH. How many atoms of each type of element are there in a molecule of leucine?
    *No numbers preceding atoms/ molecules
    A. 6 atoms of carbon, 13 atoms of hydrogen, 2 atoms of oxygen and 1 atom of nitrogen
    B. 5 atoms of carbon, 8 atoms of hydrogen, 2 atoms of oxygen and 1 atom of sodium
    C. 6 atoms of carbon, 13 atoms of hydrogen, 2 atoms of oxygen and 1 atom of natrium
    D. 8 atoms of carbon, 10 atoms of hydrogen, 2 atoms of oxygen and 1 atom of nitrogen
A

Answer is A: The number of atoms immediately follows the symbol for the element as a subscript. A number following a parenthesis multiplies the atoms inside the parenthesis. Hence there are six atoms of carbon (including two inside the parenthesis). By the same reasoning, there are 13 atoms of hydrogen (including 6 inside the parenthesis). An amino acid always has an atom of nitrogen.

47
Q
  1. What may be stated about a chemical bond between atoms that is polar? They occur:
    A. Between a metal and a non-metal atom
    B. Between two non-metal atoms
    C. Between two non-metal atoms that are different to each other
    D. When the electrons in the bond are shared equally
A

Answer is C: Choice B is wrong if the two atoms are the same, e.g. if both are oxygen. Choice D is wrong as it implies a non-polar bond.

48
Q
  1. What may be stated about a molecule that is polar?
    A. It is probably soluble in polar liquids such as lipids.
    B. The molecule has a highly symmetrical shape.
    C. It is likely to be soluble in non-polar liquids such as lipids.
    D. One end of the molecule will contain different atoms from the opposite end.
A

Answer is D: A polar molecule has opposite ends (poles) that are different from each other. That is, the molecule is not symmetrical. Choice A is wrong as lipids are not polar liquids.

49
Q
  1. Which of the following best describes the electrolytes that are dissolved in blood?
    A. Positive ions
    B. Any charged particle
    C. Molecules with an electric charge
    D. Negative ions
A

Answer is B: The term electrolyte is applied to any species of dissolved particle that has an electric charge.

50
Q
  1. The formula for the bone mineral calcium hydroxyapatite is Ca10(PO4)6(OH)2. How many atoms of each element are there in this molecule?
    *No numbers preceding atoms/ molecules
    A. 10 atoms of calcium, 6 atoms of phosphorus, 26 atoms of oxygen and 2 atoms of hydrogen
    B. 10 atoms of calcium, 6 atoms of phosphorus, 5 atoms of oxygen and 2 atoms of hydrogen
    C. 10 atoms of cadmium, 4 atoms of phosphorus, 8 atoms of oxygen and 2 atoms of hydrogen
    D. 10 atoms of calcium, 6 atoms of polonium, 1 atom of oxygen and 2 atoms of hydrogen
A

Answer is A: The number of atoms is written as a subscript and immediately follows the symbol for the element. Hence there are ten atoms of calcium. When the subscript is outside the parenthesis, it refers to all of the atoms enclosed by the paren- theses. Hence there are six atoms of phosphorus, two of hydrogen and (4 × 6)+(1 × 2) = 26 of oxygen. Ca is the symbol for calcium. Cadmium has the symbol Cd. Polonium has the symbol Po (not PO).

51
Q
  1. Urea has the formula CH4N2O. Identify the elements and how many atoms of each element are present in a molecule of urea.
    A. 1 molecule of methane and 1 of dinitrogen oxide
    B. 1 of carbon, 4 of hydrogen, 2 of nitrogen, 1 of oxygen
    C. 1 of calcium, 4 of hydrogen, 2 of ammonia, 1 of oxygen
    D. 1 of carbon, 1 of hydrogen, 4 of nitrogen, 2 of oxygen
A

Answer is B: The elements are carbon, hydrogen, nitrogen and oxygen. The sub- script number immediately after the symbol states how many of each atom there are. Hence there are four atoms of hydrogen.

52
Q
  1. Which of the following is the ion of a metal element?
    A. Na+
    B. NH4+
    C. Cl−
    D. HCO −
A

Answer is A: A metal element loses an electron in chemical reactions so that its number of protons outnumber the electrons which leaves it with a positive charge. Choice B, while being a positive ion, is a compound, not an element.

53
Q
  1. Which of the following is the ion of a non-metal element?
    A. H3O+
    B. NH4+
    C. Cl−
    D. HCO −
A

Answer is C: While all of the elements represented by symbols in the four choices are non-metals, only choice C represents an element. All others are compounds.

54
Q
  1. Which of the following is the ion of a non-metal element?
    A. K+
    B. Mg++
    C. Na+
    D. Cl−
A

Answer is D: A non-metal element gains one (or more) electron in a chemical reaction so that its number of electrons outnumbers the protons which gives it with a negative charge. The other three choices are metal elements, which result in ions with a positive charge.

Animal Course Physiology Exam (15 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions