Counting Atoms

Front

What is the formula to calculate the number of atoms in a compound?

Back

To calculate the number of atoms in a compound, multiply the subscript of each element by the coefficient in front of the compound and sum them up.

Front

How many total atoms are in the compound 3(NH₄)₂CrO₄?

Back

24 total atoms (3 * (2 H + 1 N + 4 O) = 24).

Front

What does the subscript in a chemical formula represent?

Back

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

Front

How many nitrogen atoms are in (NH₄)₂CrO₄?

Back

There are 2 nitrogen atoms.

Front

What is the significance of the coefficient in a chemical formula?

Back

The coefficient indicates how many molecules of the compound are present.

Front

How many oxygen atoms are in Al₂(SO₄)₃?

Back

There are 12 oxygen atoms.

Front

In the compound H₂C₃O₄N₅, how many carbon atoms are present?

Back

There are 3 carbon atoms.

Front

What is the total number of hydrogen atoms in 3(NH₄)₂CrO₄?

Back

There are 24 hydrogen atoms.

Front

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

Back

Multiply the number of atoms inside the parentheses by the subscript outside the parentheses.

Front

What is the total number of oxygen atoms in 3(NH₄)₂CrO₄?

Back

There are 12 oxygen atoms.