What formula do you have to use to calculate mass, the Mr or moles ?
mass = Mr x Moles
Mr = Mass/ moles
Moles = Mass/ Mr
0.5 moles of substance X has a mass of 87g. What is the relative formula mass of X?
87/0.5 = 174
What is the mass of carbon monoxide in 3.2 moles?
(Mr = 28 )
3.2x28 = 89.6
How many moles are in 156g of Al
(Al = 54, O = (16x3) 48)
54+48 = 102 156/102 = 1.5