C1-3 Chemical formula

The formula of a molecule shows the numbers of atoms of each element present. For the formula of water, H2O, how many atoms of hydrogen are there?

ANSWER USING NUMBERS NOT WORDS!

The formula of a molecule shows the numbers of atoms of each element present. For the formula of ammonia, NH3, how many atoms of hydrogen are there? ANSWER USING NUMBERS NOT WORDS!

The formula of a molecule shows the numbers of atoms of each element present. For the formula of carbon dioxide, CO2, how many atoms are there in one molecule?

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Answer explanation

There are three atoms in one carbon dioxide molecule 2 x oxygen and 1 x carbon.

How many atoms of hydrogen are there in a butane molecule?

ANSWER IN NUMBERS NOT WORDS!

What one word describes these molecules, H2, N2, O2 and Cl2?

Which of these formula is NOT correct?

• NaCl

• KO2

• CaCO3

• CaBr2

Pentene is a hydrocarbon which contains twice the number of hydrogen atoms as there are carbon atoms. If there are 5 carbon atoms what is the formula of pentene?

• C5H5

• CH5

• C5H10

• C2H4

Which shows the correct formula of calcium nitrate?

• CaNO3

• Ca3NO

• CaNO32

• Ca(NO3)2

Methane, CH4 has how many atoms in total?

ANSWER IN NUMBERS NOT WORDS!

What would be a simpler way to write the formula of pentane, CH3(CH2)3CH3?

• CH

• C3H8

• C5H10

• CH3