Răspuns :
M,Mg= 24g/mol
-calculez moli Mg
niu=m/M= 48/24= > 2molMg
-calculez moli si masa de MgO si O2 din ecuatia chimica
2mol.....1mol........2mol
2Mg + O2---> 2MgO
2mol...x=1mol.....y=2mol
niuMgO=2----> m=niuxM= 2( 24gMg + 16gO)/mol= 80gMgO
niu,O2=1mol---> m=1x32g=32gO2
CALCULEZmoli H2, O2 care au M,H2=2g/mol,M,O2=32g/mol
niu=m/M= 40/2=.20molH2
niu= 320/32=>10molO2
-calculez moli si masa O2 si H2o,din ecuatia chimica
2mol....1mol........2mol
2H2 + O2---> 2H2O
20mol..x=10mol....y=20mol
m02= niuX,M,O2= 10X32=.> 320gO2
m,H2O= 20X18=360g, deoarece M,H2O=18g/mol
total moli H2si O2=30mol
1mol substanta contine N,A= 6,023X10²³molec
30mol.......................................N= 180x10²³molec H2 si O2