5.0 mL sample of hydrogen gas is collected at a pressure of 97.5 kPa when the temperature is 18°C. Calculate the volume this gas would occupy at STP in Liters.
STP stands for Standard Temperature and Pressure. This means that the temperature is 0°C and the pressure is 101.3 kPa = 1 atm.
2. (11 pts) Balance the following equation: _____ H2 + _____ N2 → _____NH3
A. Whattypeofreactionisthis?________________________
B. Arethenumberofmolesconservedinthebalancedequation?Justifyyourreasoningin complete sentences.
C. Howdoesthebalancedequationsupportthelawofconservationofmass,ingrams?Justify your reasoning in complete sentences.
D. Howmanymolesofammonia(NH3)canbeproducedfromthereactionof4.0litersofhydrogen at 50.0oC and 1.2atm of pressure with excess nitrogen?
Ans to 2D: _____________________
Standard Pressures: 1 atm = 760 torr = 760 mmHg = 101.3 kPa = 101,300 Pa = 14.7 psi
Water Vapor Pressure Table
TP (°C) (mmHg)
TP (°C) (mmHg)
TP (°C mmHg)
0.0 4.6
5.0 6.5 10.0 9.2 12.5 10.9 15.0 12.8 15.5 13.2 16.0 13.6 16.5 14.1 17.0 14.5 17.5 15.0 18.0 15.5 18.5 16.0 19.9 16.5
19.5 17.0 20.0 17.5 20.5 18.1 21.0 18.6 21.5 19.2 22.0 19.8 22.5 20.4 23.0 21.1 23.5 21.7 24.0 22.4 24.5 23.1 25.0 23.8 26.0 25.2
27.0 26.7 28.0 28.3 29.0 30.0 30.0 31.8 35.0 42.2 40.0 55.3 50.0 92.5 60.0 149.4 70.0 233.7 80.0 355.1 90.0 525.8 95.0 633.9
100.0 760.0
3. (8 pts) Ammonium nitrite decomposes to give off nitrogen gas and liquid water. How many grams of ammonium nitrite must have reacted if 2.58 L of gas was collected over water in a gas collecting tube at 21.0oC and 97.8 kPa?
Balanced equation: _______________________________________________________________
Ans to 3: _________________
(6 pts) Will the volume of nitrogen (from the previous problem) INCREASE, DECREASE or remain the SAME if... *Explain briefly*
A. ...the experiment is done at significantly higher temperature? __________
B. ...the amount of ammonium nitrite was increased? __________
C. ...the experiment was not collected over water? __________
4. (10 pts) 900.0 mL of 3.00M phosphoric acid, H3PO4, reacts with 235 grams of iron (III) carbonate. Balanced Equation: Fe2(CO3)3 + 2H3PO4 → 2FePO4 + 3H2O + 3CO2
a. Determine the limiting reactant. Show all work!
Ans to 4a: _________________
b. How many milliters of carbon dioxide gas can be produced at 78°C at 45.5 psi pressure with 900.0 mL of 3.00M phosphoric acid and 235 grams of iron (III) carbonate?
Ans to 4b: _________________
