Chemistry Final

Which observation does NOT indicate that a chemical reaction has occurred? a. formation of a precipitate b. production of a gas c. evolution of heat and light d. change in total mass of substances

d. change in total mass of substances

The equation AX + BY -> AY + BX is the general equation for a a. single displacement reaction b. synthesis reaction c. decomposition reaction d. double-displacement reaction

d. double-displacement reaction

In what kind of reaction do two or more substances combine to form a new compound? a. decomposition reaction b. ionic reaction c. double-displacement reaction d. synthesis reaction

d. synthesis reaction

The equation AX --> A+X is the general equation for a

decomposition reaction

The reaction represented by the equation 2HgO(s) --> 2Hg(l) + O2(g) is a

decomposition reaction

The reaction represented by the equation 2KClO3(s) --> 2KCl(s) + 3O2(g) is a

decomposition reaction

The reaction represented by the equation Pb(NO3)2(aq)+2KI(aq) --> PbI2(s)+2KNO3(aq) is a

double-displacement reaction

If chlorine gas is produced by halogen replacement, the other halogen in the reaction must be

fluorine

The units of molar mass

g/mol

the replacement of bromine by chlorine in a salt is an example of a single-displacement reaction by

halogens

In most chemical reactions the amount of product obtained is

less than the theoretical yield

A chemical reaction involving substances A & B stops when B is completely used. B is the

limiting reactant

*Oxides of active metals, such as CaO, react with water to produce

metal hydroxides CaO + H2O --> CaOH

In the chemical reaction wA + xB --> yC + zD, a comparison of the number of moles of A to the number of moles of C would be a

mole ratio

A balanced chemical equation allows one to determine the

mole ratio of any two substances in the reaction

Predict what happens when zinc is added to WATER

no reaction occurs

In one type of synthesis reaction, an element combines with oxygen to yield a(n)

oxide

the coefficients in a chemical equation represents the

relative numbers of moles of reactants & products

A chemical equation is balanced when the

same number of each kind of atom appears in the reactants and in the products

The reaction represented by the equation Cl2(g) + 2KBr(aq) --> 2KCl(aq) + Br2(l) is a

single-displacement reaction

The reaction represented by the equation Mg(s) + 2HCl(aq) --> H2(g) + MgCl2(aq) is a

single-displacement reaction

The kinetic-molecular theory explains the behavior of

solids, liquids, and gases.

*stopped multiple choice here* The reaction represented by the equation 2Mg(s) + O2 (g) --> 2MgO(s) is a

synthesis reaction

What determines the average kinetic energy of the molecules of any gas?

temperature

*If the percentage yield is equal to 100%, then

the actual yield is equal to the theoretical yield

Electrolysis

the decomposition of a substance by an electric current

The reaction stops when

the limiting reactant in a chemical reaction is completely used

In the chemical reaction wA + xB --> yC + zD, if one knows the mass of A and the molar masses of A, B, C & D, one can determine

the mass of ANY of the reactants or products

To determine the limiting reactant in a chemical reaction involving known masses of A & B, one could first calculate

the number of moles of B & the number of moles of A available

Unlike in an ideal gas, in a real gas

the particles exert attractive forces on each other

Percentage yield

the ratio of the actual yield to the theoretical yield, multiplied by 100%

limiting reactant

the reactant that controls the amount of product formed in a chemical reaction

reaction stoichiometry

the study of mass relationships between reactants and products in a chemical reaction

In a double-displacement reaction, hydrogen chloride & sodium hydroxide react to produce sodium chloride. Another product is

water

What can be predicted by using an activity series?

whether a certain chemical reaction will occur

The symbol for a substance in water solution is followed by a. (l) b. (aq)

(aq)

*USING TABLE* *For the reaction represented by the equation Pb(NO3)2+2KI-->PbI2+2KNO3, how many moles of lead (II) iodide are produced from 300 g of potassium iodide and an excess of Pb(NO3)2

0.904 mol (Use KI, not 2KI aka don't use coefficients to calculate molar mass)

Which coefficients correctly balance the formula equation CaO + H2O -> Ca(OH)2

1, 1, 1

Which coefficients correctly balance the formula NH4NO2 -> N2 + H2O?

1, 1, 2

*USING TABLE* For the reaction represented by the equation Cl2+2KBr-->2KCl+Br2, how many moles of potassium chloride are produced from 119 g of potassium bromide?

1.00 mol

*USING TABLE* For the reaction represented by the equation 2H2 + O2 --> 2H20, how many grams of water are produced from 6.00 mol of hydrogen?

108 g

For the reaction represented by the equation 2H2 + O2 --> 2H2O, how many moles of water can be produced from 6.0 mol of oxygen?

12 mol

*USING TABLE* For the reaction represented by the equation 2Na + 2H20 --> 2NaOH + H2, how many grams of sodium hydroxide are produced from 3.0 mol of sodium with an excess of water?

120 g

*USING TABLE* For the reaction represented by the equation Cl2+2KBr-->2KCl+Br2, how many grams of potassium chloride can be produced from 300 g each of chlorine & potassium bromide?

188 g

In the reaction represented by the equation N2 + 3H2 --> 2NH3, what's the mole ratio of nitrogen to ammonia?

1:2

For the reaction represented by the equation C + 2H2 --> CH4, how many moles of hydrogen are required to produce 10 mol of methane, CH4?

20 mol

In the reaction represented by the equation C + 2H2 --> CH4, what's the mole ratio of hydrogen to methane?

2:1

*What is the balanced equation when aluminum reacts with copper(II) sulfate?

2Al + 3CuSO4 --> Al2(SO4)3 + 3Cu

Which reaction does not occur?

2HF(aq) + Cl2(g) -> F2(g) + 2HCl(aq)

The Haber process for producing ammonia commercially is represented by the equation N2(g) + 3H2 (g) --> 2NH3 (g). To completely convert 9.0 mol of hydrogen gas to ammonia gas, how many moles of NITROGEN gas are required?

3.0 mol

*USING TABLE* For the reaction represented by the equation SO3+H20-->H2SO4, how many grams of sulfur trioxide are required to produce 4.00 mol of sulfuric acid in an excess of water?

320 g

In the reaction represented by the equation N2 + 3H2 --> 2NH3, what is the mole ratio of nitrogen to ammonia?

3:2

*USING TABLE* For the reaction represented by the equation 2Na+2H20-->2NaOH+H2, how many grams of hydrogen are produced if 120 g of sodium and 80 g of water are available?

4.5 g

In the equation 2KClO3 -> 2KCl + 3O2, how many moles of oxygen are produced when 3.0 mol of KClO3 decompose completely?

4.5 mol

In the reaction represented by the equation 2Al2O3 --> 4Al + 3O2, what's the mole ratio of aluminum to oxygen?

4:3

*USING TABLE* For the reaction represented by the equation CH4 + 2O2 --> CO2 + 2H20, how many moles of carbon dioxide are produced from the combustion of 100 g of methane?

6.23 mol

For the reaction represented by the equation AgNO3 + NaCl --> NaNO3 + AgCl, how many moles of silver chloride, AgCl, are produced from 7.0 mol of silver nitrate AgNO3?

7.0 mol

*USING TABLE* For the reaction represented by the equation 2Na + Cl2-->2NaCl, how many grams of chlorine gas are required to react completely with 2.00 mol of sodium?

70.9 g

*USING TABLE* For the reaction represented by the equation 2Na + Cl2 --> 2NaCl, how many grams of sodium chloride can be produced from 500 g each of sodium and chlorine?

824 g

For the reaction represented by the equation N2 + 3H2 -> 2NH3, how many moles of nitrogen are required to produce 18 mol of ammonia?

9.0 mol

For the reaction represented by the equation SO3 + H2O-->H2SO4, calculate the percentage yield if 500 g of sulfur trioxide react with excess water to produce 575 g of sulfuric acid

93.9% (1. Find moles of SO3 using given grams and molar mass in mols/gram 2. Find moles of H2SO4 using given grams and molar mass in mols/gram... this is the limiting reactant because it is smaller! 3. Using moles of limiting reactant, multiply by mole ratio to find the actual yeild.

Balance C3H8(g) + O2(g) --> CO2(g) + H20(l)

C3H8(g) + 5O2(g) --> 3CO2(g) + 4H20(l)

Carbonate

CO3 charge -2

Predict what happens when calcium metal is added to a solution of magnesium chloride

Calcium chloride forms

What type of reaction is C3H8(g) + O2(g) --> CO2(g) + H20(l)

Combustion

*Write a balanced chemical equation for the following reaction: Iron plus copper (I) nitrate yields iron (II) nitrate plus copper

Fe + 2Cu(NO3) --> Fe(NO3)2 + 2Cu

In writing a chemical equation that produces hydrogen gas, the correct representation of hydrogen gas is a. H b. H2

H2

*Sulfuric Acid

H2SO4 (Strong Acid)

Predict what happens when lead is added to nitric acid

Hydrogen is released

*Magnesium bromide (aq) + chlorine (g) yields

MgCl2(aq) and Br2(l)

Nitrate

NO3 charge -1

**The formulas for the products of the reaction between sodium hydroxide & sulfuric acid are

Na2SO4 and H20

*Sodium Hydroxide

NaOH (Strong Base)

*Predict what happens when nickel is added to a solution of potassium chloride

No reaction occurs

Sulfate

SO4 charge -2

Stoichiometry

The branch of chemistry that deals with the mass relationships of elements in compounds & the mass relationships among reactants and products in chemical reactions

activity series

a list of elements arranged according to the ease with which they undergo certain chemical reactions

When a solid produced by a chemical reaction separates from the solution it is called

a precipitate

In what kind of reaction does a single compound produce two or more simpler substances? a. decomposition reaction b. synthesis reaction c. single-displacement reaction d. ionic reaction

a. decomposition reaction

In what kind of reaction does one element replace a similar element in a compound? a. displacement reaction b. ionic reaction c. decomposition reaction d. combustion reaction

a. displacement reaction

The equation A + BX --> AX + B is the general equation for a a. single-displacement reaction b. double-displacement reaction c. combustion reaction d. decomposition reaction

a. single-displacement reaction

The measured amount of a product OBTAINED from a chemical reaction

actual yield

According to the kinetic-molecular theory, particles of matter

are in constant motion.

***?According to the kinetic-molecular theory, gases condense into liquids because of

atmospheric pressure.

Which of the following is a formula equation for the formation of carbon dioxide from carbon and oxygen? a. carbon plus oxygen yields carbon dioxide b. C+O2-->CO2 c. CO2 --> C + O2

b. C+O2-->CO2

A chemical formula written over the arrow in a chemical equation signifies a. a by-product b. a catalyst for the reaction c. the formation of a gas

b. a catalyst for the reaction

What is the small whole number that appears in front of a formula in a chemical equation? a. a subscript b. a coefficient c. a ratio

b. a coefficient

In what kind of reaction do the ions of two compounds exchange places in aqueous solutions to form two new compounds? a. synthesis reaction b. double-displacement reaction c. decomposition reaction d. combustion reaction

b. double-displacement reaction

A chemical equation is balanced when the a. coefficients of the reactants = the coefficients of the products b. same number of each kind of atom appears in the reactants and in the products c. subscripts of the reactants = the subscripts of the products

b. same number of each kind of atom appears in the reactants and in the products

In a chemical reaction a. energy as heat must be added to the reactants b. the mass of the reactants equals the mass of the products c. the number of atoms in the reactants and product must change d. the mass of the products is greater than the mass of the reactants

b. the mass of the reactants equals the mass of the products

An element in the activity series can replace any element

below it on the list.

An insoluble gas that forms in a double-displacement reaction in aqueous solution

bubbles out of solution

Which equation is not balanced? a. H2+H2+O2-->H2O+H2O b. 4H2+2O2-->4H2O c. 2H2 + O2 --> H2O d. 2H2+O2-->2H2O

c. 2H2 + O2 --> H2O

How would oxygen be represented in the formula equation for the reaction of methane and oxygen to yield carbon dioxide and water? a. oxygen b. O c. O2

c. O2

Which process can be explained by the kinetic-molecular theory? a. combustion b. oxidation c. condensation d. displacement reactions

c. condensation

The equation A + X --> AX is the general equation for a a. combustion reaction b. ionic reaction c. synthesis reaction d. double-displacement reaction

c. synthesis reaction

According to the kinetic-molecular theory, which is the most significant difference between gases and liquids? a. the shapes of the particles b. the mass of each particle c. the distance between the particles d. the type of collision that occurs between particles

c. the distance between the particles

If one knows the mole ratio of a reactant and product in a chemical reaction, one can

calculate the mass of the product produced from a known mass of reactant

*When heated, a metal carbonate decomposes into a metal oxide and

carbon dioxide Ag2(CO3)-->Ag2O+CO2 VALENCE STATES: Ag (+1) Carbonate (CO3) (2-) O (-2)

To balance a chemical equation, it may be necessary to adjust the

coefficients