How many moles of water are there in 100 grams of water?

Answer 1

First you find the Molar Mass of water using the values on the Periodic Table.

2 Hydrogen + 1 Oxygen

2*1.01 + 16.00 = 18.02 g/mol

Then using factor-label to cancel out units

(100g H2O)*(1 mol H2O / 18.02 g H2O) = 5.54938957 mol

So the number of moles in 100g of H2O is about 5.55 moles.

Hope that helps.

Answer 2

1 molecule of water is composed of:

H2, with a molar mass of 2.02g, assuming 3 significant digits.

O, with a molar mass of 16.0g, assuming 3 significant digits.

Therefore, 1 mole of water (H2O) molecules has a mass of 18.0g, keeping 3 significant digits.

Then you just divide 100g by 18g, getting 5.555555...

You must keep the 3 significant digits from before, though, so you round to 5.56.

Your answer is 5.56 moles of water (H2O) in 100 grams of water (H2O).

Answer 3

For this you need the atomic (molecular) mass of H2O. Take the number of grams and divide it by the Atomic Mass. Multiply by one mole for units to cancel. H2O=18.0 grams

100.0 grams H2O / (18.0 grams) =5.56 moles H2O

Answer 4

Formula of water = H2O Relative atomic mass of hydrogen = 1

Relative atomic mass of oxygen = 16

Relative molecular mass of H2O = 1 + 1 + 16 = 18

Moles = mass of substance/relative molecular mass

Moles = 100/18

Moles of water in 100g = 5 and 4/9 moles or approximately 5.56 moles

Answer 5

100 grams water (1 mole H2O/18.016 grams)

= 5.55 moles of water

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Answer 6

100 grams water (1 mole H2O/18.016 grams)(2 moles H/1 mole H2O)

= 11.1 moles of hydrogen

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Answer 7

100 grams of H2O is equal to 5,555 moles.