Răspunsuri

2014-04-12T13:06:04+03:00
X mol   0,43mol
___      ___
2HCl + 2Na--->2NaCl + H2
____    ____
2mol     2mol

Cm=n (nr. de moli) / V => V=n/Cm
md Na= 50 * 20 /100 = 10 g Na
n Na = m / masa molara = 10 / 23     =   0,43 mol Na
x=0,43 mol HCl
V=0,43/0,1 =4,3 L
2014-04-12T13:44:19+03:00
HCl + Na ---> NaCl + 1/2 H2
c%=md/ms*100=>md=ms*c/100=20*50/100=>md=10 g
36,5 g HCl........23 g Na
x g HCl.............10 g Na     x = 15,86957 g HCl
cM=m/μ*V=>V = m/μ*cM = 15,86957/36,5 * 0,1=>V=4,3478 litri HCl