Chemistry

Question 1

Antoine Lavoisier discovered the relationship between the mass of reactants and products. How did this discovery become a scientific law?

Answer 1

Law of conservation of mass

Question 2

Lewis electron-dot diagram for sodium atom

Answer 2

Na●

Question 3

What occurs when potassium reacts with chlorine to form potassium chloride?

Answer 3

Electrons are transferred, and it becomes ionic due to the metal (K) and non-metal (Cl)

Question 4

Covalent bonds mainly occur between which types of elements?

Answer 4

Sharing electron pairs of non-metals

Question 5

What is the correct formula for the compound mercury (II) nitrate?

Answer 5

Hg (NO3)2

Question 6

Draw particle diagrams that represent pure substances and mixtures

Question 7

Draw an electron dot diagram that represents the bonding in potassium iodide

Question 8

Why can carbon form a variety of organic compounds

Question 9

Balance the equation: NH3+O2 –> NO +H2O

Question 10

Given the unbalanced equation: HCl(aq) + MnO2(s) –> H2O(l)+MnCl2(aq) + Cl2(g) What is the mole ratio of HCL to MnO2?

Question 11

Milk of magnesia contains the chemical, magnesium hydroxide, Mg(OH)2. If a bottle contains 35.0g of Mg(OH)2 and a mole contains 6.02x10^23 formula units, how many formula units of Mg(OH)2 does the bottle contain?

Question 12

According to the equation below N2O3 (g) + 6H2 (g) –> 2NH3(g) + 3H2O(g) how many moles of NH3 (g) could be formed from the reaction of 0.22 mol of N2O3 (g) with excess H2(g)?

Question 13

Given the incomplete equation representing a reaction 2H2 = O2 —> 2H2O + energy, which mass of oxygen completely balanced using the smallest whole-number coefficients?

Question 14

Given the balanced equation representing a reaction: 2H2 + O2 —> 2H2O + energy, which mass of oxygen completely reacts with 4.0 grams of hydrogen to produce 36.0 grams of water?

Question 15

What is the molar mass of Ca(OH)2?

Question 16

Which equation represents a single replacement reaction?

Question 17

What type of reaction is the following reaction classified as? NaCl + AgNO3 –> NaNO3 + AgCl

Question 18

What are the product(s) of the following reaction? HBr+Cl2 –>

Question 19

What type of reaction is represented by the following equation? 2Kl + F2 –> 2KF + l2

Question 20

Which is the product(s) of the following reaction? C2H2O + O2 –>

Question 21

Which is a reaction in which the products possess more energy than the reactants?

Question 22

Instant cold packs can help reduce swelling due to injury. These cold packs rely on a chemical reaction to become cold. Describe the energy changes that occur in this chemical reaction that makes the cold packs feel cold.

Question 23

Under which conditions is a gas most soluble in a liquid?

Question 24

According to which theory or law is a chemical reaction most likely to occur when two particles with the proper energy and orientation interact with each other?

Question 25

Given the diagram representing a closed system at constant temperature: describe the relationship between liquid water and water vapor at equilibrium

Question 26

Given the reaction H2(g) +l2(g) + 12.4kJ <—–> 2Hl (g). What conditions can be changed to shift the equilibrium to the right?

Question 27

Identify the point of equilibrium on a reaction diagram.

Question 28

Given the following reaction: H (aq) + H2O (l) —> H2O (aq), how does water behave according to acid-base theory?

Question 29

Using the base-base theory, describe the characteristics of a potassium hydroxide KOH (aq) solution.

Question 30

What units represent the concentration of a solution?

Question 31

Describe the characteristics of an electrolyte

Question 32

Water can donate a proton to become a hydroxide ion. What does water qualify as in this case?

Question 33

What is the number of moles CO2 in a 220.0-gram sample of CO2 (molar mass of CO2 = 44 g/mol)

Question 34

What is the percent composition of nitrogen in the compound N2H4? (molar mass of N2H4 = 32 g/mol)

Question 35

Given the balanced equation representing a reaction: 4NH3 + 5 O2 –> 4 NO + 6H2O, what is the number of moles of H2O formed when 2 moles of NH3 react completely?

Question 36

Given the following balanced equation FeO3+ 3CO –> 2Fe + 3CO2 How many grams are required to completely react with 84 grams of CO?

Question 37

Given the reaction KCIO3 –> 2KCL + 3O2 How many moles of KCIO3 must completely react to produce 6 moles of O2?

Question 38

How many moles are in 2.04 x 10^24 molecules of water?

Question 39

A research team conducted an investigation to establish the relationship between the concentration of a new pesticide and the health impact of the pesticide on developing fish eggs.

Question 40

The team populated five tanks with 500 fish eggs in water containing a different pesticide concentration. The number of fish eggs that developed normally in each tank and the pesticide concentrations are shown in the data table below.

Question 41

Energy is released as digestion occurs. This is an example of an exothermic reaction. Draw a potential energy diagram for an exothermic chemical reaction.

Question 42

What is the difference between saturated and unsaturated carbon compound?

Question 43

What is the difference between a chemical reaction and a nuclear reaction?

Question 44

Where does the rearrangement in nuclear reactions occur?

Question 45

What type of short-range force occurs that holds protons together?