Counting atoms

Front

What is a subscript in a chemical formula?

Back

A subscript is a small number written below and to the right of an element symbol that indicates the number of atoms of that element in a molecule.

Front

How many atoms of Sodium (Na) are present in the formula 6NaCl?

Back

6

Front

What does the formula Al₂(SO₄)₃ indicate about the number of Oxygen atoms?

Back

There are 12 Oxygen atoms in Al₂(SO₄)₃.

Front

How many atoms of Oxygen are in the molecule H₂O?

Back

1

Front

In the compound (NH₄)₂CrO₄, how many Nitrogen (N) atoms are there?

Back

2

Front

What does the coefficient in front of a chemical formula represent?

Back

The coefficient indicates the number of molecules or moles of that compound.

Front

If a chemical formula has a subscript of 3 next to an element, what does that mean?

Back

It means there are 3 atoms of that element in the molecule.

Front

In the compound C₆H₁₂O₆, how many Carbon (C) atoms are there?

Back

6

Front

What is the total number of atoms in the molecule C₁₂H₂₂O₁₂?

Back

36 atoms (12 C + 22 H + 12 O).

Front

How do you determine the number of atoms in a compound with parentheses?

Back

Multiply the subscript outside the parentheses by the subscripts of each element inside.