Flashcard #5 (Counting atoms and chemical reactions)

Front

What is a reactant in a chemical reaction?

Back

A reactant is a substance that is consumed during a chemical reaction, typically found on the left side of a chemical equation.

Front

What is the molecular formula for water?

Back

H₂O

Front

What does the coefficient in a chemical equation represent?

Back

The coefficient indicates the number of molecules or moles of a substance involved in the reaction.

Front

What does a subscript in a chemical formula indicate?

Back

A subscript indicates the number of atoms of the element in a molecule.

Front

How many hydrogen atoms are in one molecule of water (H₂O)?

Back

2

Front

What is the difference between a coefficient and a subscript?

Back

A coefficient applies to the entire molecule and indicates how many of that molecule are present, while a subscript applies only to the element it follows and indicates how many atoms of that element are in the molecule.

Front

What is the correct molecular formula for hydrogen peroxide?

Back

H₂O₂

Front

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

Back

12 oxygen atoms.

Front

If you have 3H₂O, how many total hydrogen atoms do you have?

Back

6 hydrogen atoms.

Front

What is the total number of atoms in one molecule of C₆H₁₂O₆ (glucose)?

Back

24 atoms (6 carbon, 12 hydrogen, 6 oxygen).