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## How many moles are in H2O?

The number of atoms is an exact number, the number of mole is an exact number; they do not affect the number of significant figures. The average mass of **one mole** of H2O is 18.02 grams. This is stated: the molar mass of water is 18.02 g/mol. Notice that the molar mass and the formula mass are numerically the same.

## How many H2O molecules are there in a mass of 15g?

Water has a molar mass of 18.01528 g/mol≈18 g/mol . Since water has a chemical formula of H2O , there will be 2 moles of hydrogen in every mole of water. In one mole of water, there will exist approximately **6.02⋅1023 water molecules**.

## How many moles are in 25g of water?

Hence, **1.38 moles** (mol) are present in 25 grams of water.

## How many moles are there in 10 grams of H2O?

1 mole of water weighs 18g. **10/18** moles = 10/18 * 6 * 10^23 number of molecules = 3.33 * 10^23 molecules of water. Each molecule of water has 3 atoms, so the total number of atoms in 10g of water is 3*3.33*10^23 = 10^24.

## How many moles are in 20 grams of co2?

ANSWER: **1 mole** of carbon-12 has 6.02 x 1023 atoms. Second, you need to know how many moles there are in 20 grams of carbon-12. One mole of anything is the same number of grams as the molecular mass.

## What is the formula for moles to grams?

Moles to grams example problem

Solution: Find out the molar mass of the substance (hint: you can use Molar mass of the substance alone to calculate molar mass). The molar mass of KClO3 is 122.548 g/mol. **Multiply the given number of moles** (2.50 mol) by the molar mass (122.548 g/mol) to get the grams.

## How many moles of hydrogen are in 25 moles of water?

Thus there are **2.77 moles** of hydrogen in 25 g of water.

## How many grams are in a mole?

Another property of Avogadro’s number is that the mass of one mole of a substance is equal to that substance’s molecular weight. For example, the mean molecular weight of water is 18.015 atomic mass units (amu), so one mole of water weight **18.015 grams**.