4.9 a) n1 moli CH4
n2 moli O2
(16n1 +32n2) /(n1 + n2) = 28,8 16n1 + 32n2 = 28,8n1 + 28,8n2
12,8n1 = 3,2n2 4n1 = n2
% CH4 = n1·100/5n1 = 20%
% O2 = 4n1·100/5n1 = 80%
b) n1 moli CH4
n2 moli C2H6 n1/(n1+n2) = 0,6 n1 = 0,6n1 + 0,6n2 0,4n1 = 0,6n2
n1 = 1,5n2 %CH4 = 1,5n2·100/ 2,5n2 = 60% %C2H6 = 40%
c) n1 moli H2
n2 moli N2
n3 moli NH3 (2n1 + 28n2 + 17n3)/(n1 + n2 + n3) = M = 0,3921·28,9
M = 11,33g/mol m1/m2 = 3/14 2n1/28n2 = 3/14 n1/14n2 = 3/14 n1= 3n2
(6n2 + 28n2 + 17n3) /(4n2 + n3) = 11,33
34n2 + 17n3 =45,32n2 + 11,33n3 5,67n3 = 11,32n2 n3 = 2n2
%H2 = 3n2·100 /6n2 = 50% %N2 = n2·100/6n2 = 16,66%
% NH3 = 2n2·100/6n2 = 33,33%
d) n1 moli C2H2
n2 moli CH4 26n1 + 16n2 =16,4 2n1 + n2 = 1,1 6n1 = 1,2
n1 = 0,2 moli C2H2 n2 = 0,7 moli CH4
% C2H2 = 0,2·100/0,9 = 22,22% % CH4 = 0,7·100/0,9 = 77,77%
e) M A = 42g/mol M B = 28g/mol
42n1 /28n2 = 4,5 3n1/2n2 = 4,5 3n1 = 9n2 n1 = 3n2
% A = 3n2·100/4n2 = 75% % B = n2·100/4n2 = 25%
