What is the mass of 3 1/2 moles of H20 using a conversion factor?

What is the mass of 0.5 moles of C02 using a conversion factor?

What is the mass of 4 moles of C2H6 using a conversion factors?

What is the mass of 2.25 moles of N02 using a conversion factor?

What is the mass of 3 1/2 moles of H20 using a conversion factor?

I'm not going to give you a bunch of answers to your homework. However I'll explain the first one to you, try the rest on your own and post back.

The conversion factor is derived from the atomic mass of the atoms and the molecular formula.

With H20 there are two elements. Hydrogen and Oxygen. The atomic mass of Hydrogen is 1 and the atomic mass of Oxygen is 16. The mass can be found on the periodic table and is usually the bottom number under the element. It is usually rounded accordingly:
(O = 15.99 ~ 16 || H = 1.008 ~ 1)

The molecular formula says there are 2 Hydrogen atoms and one oxygen atom in one molecule of water. Thus the molecular mass will be (1 x 2) + 16 which equals 18. This will be your conversion factor.
There are 18 grams in a mole of H20.

There are 3 1/2 moles. Multiplying the conversion factor by the quantity of moles will give you the mass asked for. So 3.5 x 18 results in 63.
There are 63 grams in 3 1/2 moles of H2O.

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