Question

Calculați numarul de moli corespunzator maselor urmatoare:
1. 25g de NaCl
2. 125g de H2SO4
3. 100g de KMnO4
4. 74g de KCl
5. 35g de NH3

Answer 1

υ= m/M

1. M(NaCl)=23+35.5=55.5g/mol
m(NaCl)=25g
υ(NaCl)= 25g/55.5g/mol=0.45g

2.M(H2SO4)=1*2+32+16*4=2+32+64=98g/mol
υ(H2SO4)=125g/98g/mol=1.275mol

3.M(KMnO4)=39+55+16*4=39+55+64=158g/mol
υ(KMnO4)=100g/158g/mol=0.63mol

4.M(KCl)=39+35.5=74.5g/mol
υ(KCl)=74g/74.5g/mol=0.99mol

5.M(NH3)=14+1*3=14+3=17g/mol
υ(HN3)=35g/17g/mol=2.05mol