Chlorinetrifluoride,ClF3,isavaluablereagentbecauseitcanbeusedtoconvertmetaloxidestometalfluorides:6NiO(s)+4ClF3(g)6NiF2(s)+2Cl2(g)+3O2(g)(1)WhatmassofNiOwillreactwithClF3gasifthegashasapressureof2

Question

Chlorine trifluoride,ClF3,is a valuable reagent because it can be used to convert metal oxides to metal fluorides:
6 NiO(s) + 4 ClF3(g)  6 NiF2(s) + 2 Cl2(g) + 3 O2(g)
(1) What mass of NiO will react with ClF3 gas if the gas has a pressure of 250 mm Hg at 20ºC in a 2.5-L flask?
(2) If the ClF3 described in part (a) is completely consumed,what are the partial pressures of Cl2 and O2 in the 2.5-L flask at 20ºC (in millimeters of mercury)?What is the total pressure in the flask?

Answer 1

1、
ClF3的物质的量 n = pV/RT = 250/760*101325 × (2.5/1000) ÷ 8.314 ÷ 293 mol = 0.0342 mol
NiO的物质的量 = 0.0342 * 6 / 4 mol = 0.0513 mol
NiO的质量 = 0.0513 * (59+16) g = 3.85 g
2、
生成Cl2的物质的量 = 0.0342 * 2 / 4 = 0.0171 mol
Cl2的分压 p = nRT/V = 0.0171×8.314×293 ÷ (2.5/1000) / 101325*760 = 125.0 mmHg
生成O2的物质的量 = 0.0342 * 3 / 4 = 0.0257 mol
Cl2的分压 p = nRT/V = 0.0257×8.314×293 ÷ (2.5/1000) / 101325*760 = 187.8mmHg
总压 = 125.0+187.7 = 312.7 mmHg