Question

1. What volume of fluorine gas is produced when 0.496 mol of bromine trifluoride reacts completely according to the following reaction at 0 C and 1 atm?

Bromine trifluoride (g) ——> bromine(g) + fluorine (g)

_____liters fluorine gas

2. How many moles of nitrogen gas are required to react completely with 30.6 L of oxygen gas according to the following reaction at 0 C and 1 atm?

nitrogen (g) + oxygen (g) ——> nitrogen monoxide (g)

______moles nitrogen gas

3. A mixture of neon and krypton gases at a total pressure of 836 mm Hg contains neon at a partial pressure of 265 mm Hg. If the gas mixture contains 2.05 grams of neon, how many grams of krypton are present?

Answer 1

1. Given conditions(0^oC and 1 atm ) are STP conditions so at STP , 1 mole of any gas occupies 22.4 L

The balanced equation is : 2BF₃(g) -----> Br₂(g) + 3F₂(g)

2 moles of BF3 produces 3 moles of F2

0.496 moles of BF3 produces (0.496x3)/2 = 0.744 moles of F2

1 mole of F2 occupies 22.4 L

0.744 moles of F2 occupies 0.744x22.4 = 16.7 L

2. The balanced reaction is N2 (g) + O2(g) ---> 2NO(g)

22.4 L of O2 contained in 1 mole

30.6 L of O2 contained in (30.6x1)/22.4 = 1.37 moles

Since the number of moles of O2 = number of moles of N2

So number of moles of N2 = 1.37 moles