-calculez masa de K2O din 5g cenusa
100g cenusa.....................20g oxid
5g........................................m=1g oxid
M,K2O= 94g/mol
M,HCl= 36,5g/mol
-calculez masa de acid ce reactioneaza cu 1 g oxid
1mol....2mol
K2O+ 2HCl---> 2KCl +H2O
94g.......73g
1g...........m= 0,7765 g HCl
- calculez masa de solutie ce contine aceasta masa de acid
c= mdx100/ms---> ms=mdx100/c= 0,7765x100/16=....................calculeaza !!!