Question

Suppose you have two samples that are equal in weight, 14.8 g Ti and 14.8 g Cr, 0, Calculate the number of moles of each substance. Cr,0,-

Answer 1

1)

Molar mass of Ti = 47.87 g/mol

mass(Ti)= 14.8 g

use:

number of mol of Ti,

n = mass of Ti/molar mass of Ti

=(14.8 g)/(47.87 g/mol)

= 0.3092 mol

Answer: 0.309 mol

2)

Molar mass of Cr2O3,

MM = 2*MM(Cr) + 3*MM(O)

= 2*52.0 + 3*16.0

= 152 g/mol

mass(Cr2O3)= 14.8 g

use:

number of mol of Cr2O3,

n = mass of Cr2O3/molar mass of Cr2O3

=(14.8 g)/(1.52*10^2 g/mol)

= 9.737*10^-2 mol

Answer: 9.74*10^-2 mol