Chm 104 Ch 4

Choose the best classification of the reaction represented by the following equation: MgO(s) + CO2(g) → MgCO3(s)

combination

Choose the best classification of the reaction represented by the following equation: 2KClO3(s) → 2KCl(s) + 3O2(g)

decomposition

How is the reaction shown below best classified? 2HgO(s) → 2Hg(l) + O2(g)

decomposition

Choose the best classification of the reaction represented by the following equation: BaCl2(aq) + K2SO4(aq) → BaSO4(s) + 2KCl(aq)

double-replacement

Choose the best classification of the reaction represented by the following equation: Na2SO4(aq) + Ba(OH)2(aq) → BaSO4(s) + 2NaOH(aq)

double-replacement

Which has the greatest mass, one atom of carbon, one atom of hydrogen, or one atom of lithium?

one atom of carbon

Classify the following reaction: Ce4+(aq) + Fe2+(aq) → Ce3+(aq) + Fe3+(aq)

oxidation - reduction

Choose the best classification of the reaction represented by the following equation: 2Fe3+(aq) + Fe(s) → 3Fe2+(aq)

oxidation-reduction

What is the general term for the process in which one or more electrons are transferred from one reactant to another?

oxidation-reduction

Choose the best classification of the reaction represented by the following equation: Pb(NO3)2(aq) + CaCl2(aq) → PbCl2(s) + Ca(NO3)2(aq)

precipitation

How is the reaction shown below best classified? 2NaCl(s) + F2(g) → 2NaF(s) + Cl2(g)

single-replacement

Consider the chemical equation shown below. How many moles of oxygen gas are needed to react with hydrogen to form one mole of water? 2H2(g) + O2(g) → 2H2O(l)

0.5 mol

How many moles of hydrogen gas are needed to react with oxygen to form one mole of water? 2H2(g) + O2(g) → 2H2O(l)

1 mol

How many aspirin molecules are present in a 0.325 g sample of aspirin? [Molar mass: aspirin, 180.2 g/mol]

1.09 × 10^21 molecules

How many molecules are present in a 0.0200 mol sample of nicotine?

1.20 × 1022 molecules

A sample of aluminum contains 2.91 × 1022 atoms of aluminum. What is the mass of this sample? [Molar mass: Al, 26.98 g/mol]

1.30 g

Dinitrogen monoxide, or laughing gas (N2O), is used as a dental anesthetic and as an aerosol propellant. How many molecules of N2O are present in a 12.6 g sample of the compound?

1.72 × 1023 molecules

Aspirin is the common name for acetyl salicylic acid, C9H8O4. One tablet contains 0.325 g of aspirin. How many moles of aspirin is this?

1.80 × 10-3 mol

Diamond is a pure form of the element carbon. If a 2 carat diamond has a mass of 0.396 g, how many carbon atoms are contained in this diamond?

1.99 × 1022 atoms

Incomplete combustion occurs when there is insufficient oxygen to react with a compound. The suffocating gas carbon monoxide is a product of incomplete combustion. How many moles of oxygen gas are required for the complete combustion of 11.0 moles of C6H14, a component of gasoline? C6H14(l) + 19O2(g) → 12CO2(g) + 14H2O(l)

105 mol O2

What is the mass of 4.35 moles of aluminum?

117 g

What is the mass of one mole of carbon atoms?

12.01 g

The unbalanced equation for the combustion of octane, a component of gasoline, is shown below. What would be the coefficient of carbon dioxide once the equation is balanced? C8H18(l) + O2(g) → CO2(g) + H2O(l)

16

The chemical equation below is unbalanced. What is the coefficient of water when the equation is balanced? Mg(OH)2(s) + HCl(g) → MgCl2(s) + H2O(l)

2

What is the mass of one mole of diatomic hydrogen, H2?

2.02 g

What is the mass of 3.5 × 1022 molecules of CO2?

2.6 g

Hydrogen fluoride will react with glass (silicon dioxide, SiO2) according to the equation below. What mass of HF is required to react completely with 16.0 g of glass?[Molar masses: Si, 28.09 g/mol; F, 19.00 g/mol; H, 1.01 g/mol; O, 16.00 g/mol] 4HF(g) + SiO2(s) → SiF4(g) + 2H2O(g)

21.3 g

The fluoride rinse in dental offices usually contains sodium fluoride. Sodium fluoride can be prepared from the reaction between sodium metal and fluorine gas. Which of the following properly represents the balanced chemical equation for this reaction?

2Na(s) + F2(g) → 2NaF(s)

A sample of sulfur contains 1.81 × 1024 atoms of sulfur. How many moles of sulfur does this represent?

3.01 mol

What is the mass of a 0.0200 mol sample of nicotine? [Formula mass: nicotine, 162.2 amu]

3.24 g

How many iron atoms are present in 0.552 mol of iron?

3.32 × 1023

How many molecules of water are present in a 5.65 mole sample of water?

3.40 × 10^24 molecules

The mass of one atom of oxygen is 16.00 amu. What is the mass of one mole of elemental oxygen (O2)?

32.00 g

The chemical equation below is not balanced. What is the coefficient of iron when the equation is balanced with smallest whole number coefficients? Fe(s) + O2(g) → Fe2O3(s)

4

What is the mass of a 0.150 mole sample of sulfur?

4.81 g

Methanol (CH3OH) is the fuel used by racecars in the Indianapolis 500. It burns in the engine according to the equation below. How many moles of oxygen gas are necessary to react completely with 12.5 L of methanol? [Density: CH3OH, 0.7910g/mL; Molar mass: CH3OH, 32.05 g/mol] 2CH3OH(l) + 3O2(g) → 2CO2(g) + 4H2O(g)

463 mol

When the equation below is balanced with the lowest possible whole number coefficients, what is the sum of the coefficients? Ca(s) + HCl(g) → CaCl2(s) + H2(g)

5

One mole of any substance contains Avogadro's number of particles of that substance. What is the numerical value of Avogadro's number?

6.022 ×10^23

Magnesium hydroxide, Mg(OH)2, as "Milk of Magnesia" can be used to neutralize excess stomach acid, represented by HCl(aq) according to the chemical equation below. Mg(OH)2(s) + 2HCl(aq) → MgCl2(aq) + 2H2O(l) When 5.00 g of HCl are combined with an excess of Mg(OH)2, what mass of MgCl2 can be produced? [Molar masses: H, 1.01 g/mol; O, 16.00 g/mol; Mg, 24.31 g/mol; Cl, 35.45 g/mol]

6.53

Consider the hypothetical reaction: 3A2 + 2B → C + 2D When 25 g of reactant A and 34 g of reactant B are combined, the theoretical yield of product C is 31 g. If the actual yield of product C is 19 g, what is the percent yield of C?

61%

The average mass of one atom of copper is 63.55 amu. What is the mass of Avogadro's number of copper atoms?

63.55 g

Methanol (CH3OH) is the fuel used by racecars in the Indianapolis 500. It burns in the engine according to the equation below. How many moles of oxygen gas are necessary to react completely with 425 moles of methanol? 2CH3OH(l) + 3O2(g) → 2CO2(g) + 4H2O(g)

638 mol

Glucose (C6H12O6) is an important energy-rich compound produced by photosynthesis according to the equation below. What mass of glucose can be produced from 2.61 mol of CO2 and the necessary water? [Molar masses: C, 12.01 g/mol; H, 1.01 g/mol; O, 16.00 g/mol] 6CO2(g) + 6H2O(l) → C6H12O6(l) + 6O2(g)

78.4 g

What mass of sodium hydroxide is necessary to react with a solution containing 73.00 g HCl, according to the chemical equation below? [Molar masses: NaOH, 39.99 g/mol; HCl, 36.45 g/mol] NaOH(aq) + HCl(aq) → NaCl(aq) + H2O(l)

80.09 g

What is the mass of 3.01 mol of sulfur atoms?

96.5 g

Consider the two beakers labeled A and B. Beaker A contains 1 mole of iron atoms, and Beaker B contains 1 mole of lead atoms. Which statement concerning these samples is known with certainty? (Beaker A: 1 mol Fe)(Beaker B: 1 mol Pb)

Beakers A and B contain an equal number of atoms.

Select the ionic compound that is insoluble in water.

MgS

The chemical equation below is not balanced. Balance the equation, then determine which statement concerning the balanced equation is TRUE. KClO3(s) → KCl(s) + O2(g)

The balanced equation will have two atoms of chlorine on each side.

Aluminum metal and oxygen gas are produced when aluminum oxide is heated at high temperature. Which statement concerning this chemical change is true?

This reaction is a decomposition reaction.

To convert a given number of moles into the number of atoms, one would multiply by which of the following factors?

To convert a given number of moles into the number of atoms, one would multiply by which of the following factors?

In an acid-base reaction, what is transferred from the acid to the base?

a hydrogen cation, H+

Choose the best classification of the reaction represented by the following equation: HBr(aq) + KOH(aq) → KBr(aq) + H2O(l)

acid-base

Classify the following reaction: H2SO4(aq) + 2KOH(aq) → K2SO4(aq) + 2H2O(aq)

acid-base reaction