Question

Calculeaza masa de substanta din:
a) 2,5 moli oxigen
b) 0,5 kmoli acid azotic
c) 5 moli iod
d) 3 kmoli oxid de calciu
e) 10 moli carbonat de sodiu

Ajutati-ma macar la câteva!​

Answer 1

Explicație:

1 mol oxigen........16g

2.5 moli oxigen.........x

x= 16×2,5=40g

0,5 kmoli= 0,5×1000= 500moli

M HNO3 (3 trb scris în dreapta jos)= 1+14+3×16=15+48=63g/mol

1 mol HNO3......63g

500moli.............x

x=63×500=31500g=31,5 kg

1 mol I........127g

5 mol I..........x

x=127×5=635g

3 kmoli=3000moli

M CaO=16+40=56 g/mol

1 mol CaO.........56 g

3000 moli CaO........x

x=56×3000=168000g=168kg

M Na2CO3= 2×23+40+3×16=46+40+48=86+48=134g/mol

1 mol Na2CO3..........134g

10 moli.................x

x=134×10=1340g