| 2 KClO3 >> 2 KCl + 3 O2
T = 24.2 + 273 =297.2 K
p = 768 / 760 =1.01
moles O2 = pV / RT = 1.01 x 0.9505 / 0.0821 x 297.2 =0.03967
the ratio between KClO3 and O2 is 2 : 3
Moles KClO3 = 0.03967 x 2 / 3 =0.02645
Mass KClO3 = 0.02645 mol x 122.553 g/mol =3.242 g
% = 3.242 x100 / 5.000 =64.83 |