Question

un amestec cu masa de 18.2 grame cupru cu aluminiu se trateaza cu o solutie de acid clorhidric de concentratie 16.5% in urma reactiei se degaja 0.2 moli de gaz
a)scrieti ecuatia reactiei chimice
b)masa de solutie de acid clorhidric
c) procentele de masa ale celor doua metale
d)numar de molecule gaz
multumesc anticipat

Answer 1

a) Al + 3 HCl => AlCl3 + 3/2 H2
b) 3/2 moli H2........3*36.5 g HCl
0.2 moli H2..................x g HCl
x = 14.6 g HCl
c = md/ms*100 => ms = 14.6/16.5 * 100 = 884.84 g solutie HCl
c) 27 g Al............3/2 moli H2
x g Al...................0.2 moli
x = 3.6 g Al
m Cu = 18.2 - 3.6 = 14.6 g Cu
%Cu = 14.6/18.2 * 100 = 80.219%
%Al = 3.6/18.2 * 100 = 19,780%
d) n = nr molecule/nr lui Avogadro
nr molecule = 0,2 * 6.022 * 10^23 = 1,2044 * 10^23 molecule H2