Converting Moles to Grams and Vice Versa: Potassium Sulfide and Barium Nitride

[tommyjohn]

Homework Statement

How many grams are there in 6.80 moles of potassium sulfide? How many moles are there in 200g of barium nitride?

Homework Equations

I just want to see if i got the right answer

The Attempt at a Solution

for part A. i got 759g by multiplying 6.80x110.24(molar mass of K2S)

part B. 0.455 mol by dividing 200?439.99(molar mass of Ba3N2)

 

[Borek]

6.80*110.24 is not 759

But that's probably a typo.

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[CFDFEAGURU]

From "Thermodynamics An Engineering Approach" by Cengel and Boles, "Molar mass can be defined as the mass of one mole of a substance in grams, or the mas of one kmol (kilogram-mole) in kilograms." then they go on to say "The mass of a system is equal to the product of it's molar mass M and mole number N."

You should be able to get it on your own now.

Thanks
Matt