n = N / N.A (N.A = nr.lui Avogadro = 6,023x10^23)
=> n = 1.2046 x 10^23 / 6,023x10^23 = 0,2 moli Mg
0,2 moli..md ........................ V L
Mg + 2HCl --> MgCl2 + H2
1 ........2x36,5 .................... 22,4
a)
=> md = 0,2x2x36,5 / 1 = 14,6 g HCl
c% = mdx100/ms => ms = mdx100/c% => ms = 14,6x100/20 = 73 g sol HCl
b)
=> V = 0,2x22,4/1 = 4,48 L H2
c)
n = V/Vm = N/N.A => N = VxN.A/Vm = 4,48x6,023x10^23 / 22,4 = 0,12044x10^23 sau 1,2044x10^22 atomi