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 oxygen are in the compound Al₂(SO₄)₃?

Back

There are 12 atoms of oxygen in Al₂(SO₄)₃.

Front

What elements are represented in the chemical formula Fe₂O₃?

Back

The elements represented are Iron (Fe) and Oxygen (O).

Front

How many magnesium atoms are present in 10MgCl₂?

Back

There are 10 magnesium atoms in 10MgCl₂.

Front

How many total atoms are in the molecule H₂SO₄?

Back

There are 7 total atoms in H₂SO₄.

Front

What does the chemical formula H₂O represent?

Back

H₂O represents water, consisting of 2 hydrogen atoms and 1 oxygen atom.

Front

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

Back

Coefficients indicate the number of molecules or moles of a compound in a chemical reaction.

Front

How do you determine the total number of atoms in a chemical formula?

Back

Add the subscripts of each element in the formula to find the total number of atoms.

Front

What is the difference between an element and a compound?

Back

An element is a pure substance made of one type of atom, while a compound is made of two or more different types of atoms chemically bonded together.

Front

What is the formula for calculating the number of atoms in a compound?

Back

The number of atoms = sum of all subscripts in the chemical formula.