1. Nitrogen gas and sodium liquid are produced by the decomposition of sodium azide NaN3 (s). what volume of nitrogen gas, measured at 25 C and 0.980 atm, is produced by the decomposition of 62.5 g of sodium azide?
2. A gas sample in a container with a volume “V” at a temperature “T” with a total number of moles “n”, has 76.8 mole percent N2 (g), 20.1 mole percent O2 (g), and 3.1 mole percent CO2 (g). if the ratio nRT/V is equal to 1.002, what are the partial pressures of the three gases?
3. A liquid hydrocarbon (Cx Hy) is found to be 16.37% H by mass. A 1.158-g vaporized sample of the hydrocarbon has a 358 mL volume at 71.0 C and 749 mmHg. what is the molecular formula for this hydrocarbon?
4. A 1.00 g Sample of C7H603 (s), us completely burned in a bomb calorimeter assembly by a temperature increase of 5.80 C is noted. when the calorimeter absorbs 9.37 Kj of heat, its temperature increases by 2.48 C.
-what is the heat capicity of the calorimeter?
- what is the amount of heat given off when 1 mole of C7H6O3 (s) burned? (use qcal= C cal x delta T cal)
5. given that
N2 05 + H2O (l) ---> 2HNO3 (l) delta H = -73.7 KJ
2H2 (g) + 02 (G) ---> 2H2O (L) delta H = -571. 6 KJ
N2 (g) + 3O2 (g) + H2 (g) ---> 2HNO3 (L) delta H = -348.2 KJ
Calculate delta H final (standard enthalpy of formation) if dinitrogen pentoxide gas.
6. A gass effuse 1.55 times fatser than propane C3H8 (g) at the same temperature and pressure.
- is the gas heavier or lighter than propane?
- what is he molar mass of this gas?
5 answers
1. Write the equation and balance it.
2. Convert 62.5 g NaN3 to moles. moles = grams/molar mass
3. Using the coefficients in the balanced equation, convert moles NaN3 to moles of the product, N2.
4. Use PV = nRT, substitute n for number of moles and P and T conditions in the problem calculate volume.
Pleas help with the 2nd
A gas sample in a container with a volume “V” at a temperature “T” with a total number of moles “n”, has 76.8 mole percent N2 (g), 20.1 mole percent O2 (g), and 3.1 mole percent CO2 (g). if the ratio nRT/V is equal to 1.002, what are the partial pressures of the three gases?
0.768 for N2
0.201 for O2
0.031 for CO2
PV = nRT and rearranged it is
P = nRT/V which the problem tells us 1.002.
PN2 = mole fraction N2 * 1.002 (in atmospheres.
PO2 = mole fraction O2*1.002 atm
PCO2 = mole fraction CO2*1.002 atm.
so it is
n2 ---> (76.8/100)x (1.002)!!!
ok...great can u help me with 3, 4, and 5 please if u be so generous