Counting Atoms REVIEW

Front

What is a coefficient in a chemical formula?

Back

A coefficient is a number written in front of a chemical formula that indicates how many molecules or atoms of that substance are present.

Front

What does a subscript indicate in a chemical formula?

Back

A subscript is a number written to the lower right of an element symbol that indicates how many atoms of that element are in a molecule.

Front

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

Back

12

Front

How many oxygen atoms are in Fe(NO₃)₃?

Back

9

Front

Where are coefficients found in chemical formulas?

Back

Coefficients are found at the beginning of a formula and multiply everything in the formula.

Front

What is the purpose of subscripts in chemical formulas?

Back

Subscripts indicate the number of atoms of each element in a compound.

Front

How do you calculate the total number of atoms in a compound?

Back

Add the number of atoms of each element, taking into account coefficients and subscripts.

Front

What is the difference between a coefficient and a subscript?

Back

A coefficient applies to the entire formula, while a subscript applies only to the element it follows.

Front

If a chemical formula has a coefficient of 3 in front of it, what does that mean?

Back

It means there are three times as many molecules of that compound.

Front

In the formula C₆H₁₂O₆, how many hydrogen atoms are present?

Back

12