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 Magnesium are in 10MgCl₂?

Back

10

Front

How many atoms of Oxygen are in H₂O?

Back

1

Front

What is the difference between an element and a compound?

Back

An element is a pure substance made of only one type of atom, while a compound is a substance formed when two or more different types of atoms bond together.

Front

How many atoms of Hydrogen are in 4H₂O?

Back

8

Front

What does the formula CaSO₄ represent?

Back

It represents a compound, specifically Calcium Sulfate.

Front

What does the coefficient in a chemical formula indicate?

Back

The coefficient indicates the number of molecules or formula units of a substance.

Front

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

Back

6 (2 Hydrogen atoms per molecule × 2 molecules + 1 Oxygen atom per molecule × 2 molecules = 6 total atoms).

Front

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

Back

Total atoms = (number of atoms of element 1 × coefficient) + (number of atoms of element 2 × coefficient) + ...

Front

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

Back

The chemical formula provides information about the types and numbers of atoms in a compound.