Question

determina masa de hidrogen din :
a)36 g apa
b)3,4 kg amoniac
c)6,023 x 10 la puterea 22. molecule acid clorhidric

Answer 1

a) M H2O= 2*1+16=18
18g H2O.................2g H................16g O
36g H2O..................x g H
 x= 36*2 / 18=4 g H
b)M NH3=14+3*1=17
17g NH3............3g H.............14gN
3400g NH3........xg H
x=3400*3 / 17=600g H
c) nr.moli= N/ NA( nr.particule(atomi, ioni, molecule) / nr.lui Avogadro)
n= 6,023*10 la puterea 22 / 6,023*10 la puterea 23= 10 la puterea (22-23)= =10 la puterea (-1)= 0,1moli HCl
M HCl=1+35,5= 36,5
n= m /M
m= n*M= 0,1*36,5=3,65g HCl
36,5 g HCl..............1g H...........35,5 g HCl
3,65g HCl................x g H
x=3,65*1 / 36,5=0,1g H