Show:
Chapter 7
Chapter 8
Chapter 9
200

Complete and balance each of the following chemical equations: 

  1. single replacement: Fe3O4 s+H2 g→

  2. combustion: C4H10 g+O2 g→Δ

  3. combination: Al s+O2 g→

  4. double replacement: NaOH aq+ZnSO4 aq→




1.  Fe3O4 s+4H2 g→3Fe s+4H2O g

2. C4H10g+13O2g→Δ8CO2g+10H2Og

3. 4Als+3O2g→2Al2O3s

4. 2NaOHaq+ZnSO4aq→ZnOH2s+Na2SO4aq


200

A sample of hydrogen H2 gas at 127 °C has a pressure of 2.00 atm. At what final temperature, in degrees Celsius, will the pressure of the H2 decrease to 0.25 atm, if volume and amount of gas do not change?

 −223 °C



300

Write the correct formulas for the reactants and products, the balanced equation for each of the following reaction descriptions, and identify each type of reaction: 

  1. An aqueous solution of lead(II) nitrate is mixed with aqueous sodium phosphate to produce solid lead(II) phosphate and aqueous sodium nitrate.

  2. Gallium metal heated in oxygen gas forms solid gallium(III) oxide.

  3. When solid sodium nitrate is heated, solid sodium nitrite and oxygen gas are produced.

A. 3PbNO32 aq+2Na3PO4 aq→Pb3PO42 s+6NaNO3 aq double replacement

  1. 4Ga s+3O2 g→Δ2Ga2O3 s combination

  2. 2NaNO3 s→Δ2NaNO2 s+O2g decomposition

300

 Nitrogen dioxide reacts with water to produce oxygen and ammonia. A 5.00-L sample of H2Og reacts at a temperature of 375 °C and a pressure of 725 mmHg. How many grams of NH3 can be produced? 

4NO2g+6H2Og → 7O2g+4NH3g



1.02 g of NH3



300

In a laboratory experiment, a 10.0-mL sample of NaCl solution is poured into an evaporating dish with a mass of 24.10 g. The combined mass of the evaporating dish and NaCl solution is 36.15 g. After heating, the evaporating dish and dry NaCl have a combined mass of 25.50 g. 

  1. What is the mass percent (m/m) of the NaCl solution?

  2. What is the molarity (M) of the NaCl solution?

  3. If water is added to 10.0 mL of the initial NaCl solution to give a final volume of 60.0 mL, what is the molarity of the diluted NaCl solution?


  1. 11.6% (m/m) NaCl solution

  2. 2.40 M NaCl solution

  3. 0.400 M NaCl solution

400

The combustion of propane C3H4 releases heat when it burns according to the following equation:


C3H4g+4O2g→Δ3CO2g+2H2Og


  1. How many moles of O2 are needed to react completely with 0.225 mole of C3H4?

  2. How many grams of H2O are produced from the complete reaction of 64.0 g of O2?

  3. How many grams of CO2 are produced from the complete reaction of 78.0 g of C3H4?

  4. If the reaction in part c produces 186 g of CO2, what is the percent yield of CO2 for the reaction?

  • 0.900 mole of O2

  • 18.0 g of H2O

  • 257 g of CO2

  • 72.4%

400

A gas mixture contains oxygen and argon at partial pressures of 0.60 atm and 425 mmHg. If nitrogen gas added to the sample increases the total pressure to 1250 Torr, what is the partial pressure, in torr, of the nitrogen added? 

370 Torr

400

Write the net ionic equation to show the formation of a solid (insoluble ionic compound) when the following solutions are mixed. Write none if no solid forms.

  1. AgNO3aq and LiBr(aq)

  2. NaCl(aq) and KNO3aq

  3. Na2SO4aq and BaCl2aq


  1. Ag+aq+Br−aq → AgBrs

  2. none

  3. Ba2+aq+SO42−aq → BaSO4s


500

 

Sulfur trioxide decomposes to sulfur and oxygen.

2SO3g→2Ss+3O2g

ΔH=+790 kJ


  1. Is the reaction endothermic or exothermic?

  2. How many kilojoules are required when 1.5 moles of SO3 reacts?

  3. How many kilojoules are required when 150 g of O2 is formed?

  • endothermic

  • 590 kJ

  • 1200 kJ

500

A gas mixture with a total pressure of 2400 Torr is used by a scuba diver. If the mixture contains 2.0 moles of helium and 6.0 moles of oxygen, what is the partial pressure, in torr, of each gas in the sample?

He 600 Torr, O2 1800 Torr

500

What is the molarity of a solution containing 8.0 g of NaOH in 400. mL of NaOH solution?

0.50 M NaOH solution