Count atoms in molecular formulas

Front

What is a molecular formula?

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A molecular formula shows the number and type of atoms in a molecule, using chemical symbols and subscripts.

Front

How do you count atoms in a molecular formula?

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To count atoms, look at the subscripts in the formula. The subscript indicates how many of that atom are present. If there is no subscript, it means there is one atom.

Front

In the formula H2O, how many hydrogen atoms are there?

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There are 2 hydrogen atoms in H2O.

Front

In the formula C3H8, how many carbon atoms are there?

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There are 3 carbon atoms in C3H8.

Front

What does the subscript in a molecular formula indicate?

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The subscript indicates the number of atoms of the element in the molecule.

Front

In the formula NaCl, how many sodium (Na) atoms are there?

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There is 1 sodium atom in NaCl.

Front

In the formula 2H2O, how many total hydrogen atoms are there?

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There are 4 hydrogen atoms in 2H2O (2 molecules x 2 hydrogen atoms each).

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What is the molecular formula for sulfuric acid?

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The molecular formula for sulfuric acid is H2SO4.

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How many oxygen atoms are in the formula C6H12O6?

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There are 6 oxygen atoms in C6H12O6.

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In the formula 3CO2, how many carbon atoms are there?

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There are 3 carbon atoms in 3CO2.