a) ro = m/V=>m = 0,79 * 20 * 1000(1l=1000 cm cubi) = 15,8 kg solutie
c%=md/ms * 100=>md=15,8 * 96 /100 = 15,168 lg metanol
la 32 g metanol........30 g aldehida
la 15,168 kg metanol..........x kg aldehida x = 14,22 kg aldehida
b)c%=md/ms * 100=>masa formol = 40 * 14,22 / 100 => masa formol = 0,5688 kg