1. 2g of helium, 3g of nitrogen and introduced into a 15dm^3 vessel at 100'c
a. what are the mole fractions of He ,N2, Ar in the system
b. find the total pressure of the system, and the partical pressure of He ,N2, Ar .
2. 5g of sulphur forms 10g of an oxide on complete combustion.What is the empirical formula of the oxide?
3. 19.8g of element M combines25.16g of oxygen to form an oxide.if the relative atomic massof M is 31.0. Find the empirical formula of the oxide
f.6 CHEM--mole conconcept
2008-09-14 6:56 am
回答 (2)
2008-09-14 8:42 am
✔ 最佳答案
Assume there is no Ar(a) no of mole of He = 2/4 = 0.5 mol
no of mole of N2 = 3/28 =0.1071 mol
mole fractions of He = 0.5/(0.5+0.1071) = 0.824
mole fractions of N2 = 0.1071/(0.5+0.1071) = 0.176
(b) PV=nRT
total pressure = nRT/V = (0.5+0.1071)(8.314)(100+273)/(15/1000)=1.26x10^5 Nm^-2
partical pressure of He = 1.26x10^5x0.824 = 1.03x10^5 Nm^-2
partical pressure of N2= 1.26x10^5x0176 = 2.21x10^4 Nm^-2
_________________________________________________________
S+nO2→SO(n/2)
no of mole of SO(n/2) = no of mole of S = 5/32.1 = 0.15576mol
0.15576 = mass / molar mass = 10/(32.1+16 n/2)
n=4.0
empirical formula is SO2
_________________________________________________________
no of mole of M = 19.8/31.0 = 0.63871 mol
no of mole of O2 = 25.16/32 = 0.78625 mol
no of mole of M: no of mole of O2 = 0.63871 : 0.78625 = 4:5
empirical formula is M4O5
參考: myself
2008-09-14 7:21 am
In 1, what is the amount of argon added to the flask ?
收錄日期: 2021-04-23 23:07:25
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20080913000051KK02597