Chemical formula

The chemical formula of potassium sulphate is .........

• K₂SO₄

• KSO₄

• K₃SO₃

• KSO₃

Write chemical formula of ammonium sulphate.

Which of the following ionic compounds has an incorrect formula?

• NaF₂

• AlCl₃

• Ca(NO₃)₂

• KOH

What is the formula for iron(III) chloride?

• FeCl

• FeCl₂

• FeCl₃

• Fe₃Cl

Iron(II) sulfate is composed of Fe²⁺ and SO₄^2– ions. In order to form a neutral salt, what must the ratio between the two ions be?

• Fe²⁺ : SO₄^2– = 1 : 2

• Fe²⁺ : SO₄^2– = 4 : 1

• Fe²⁺ : SO₄^2– = 1 : 1

• Fe²⁺ : SO₄^2– = 1 : 4

What is the chemical formula for a molecule composed of 2 atoms of carbon, 4 atoms of hydrogen, and 1 atom of oxygen?

• C₂H₄O₁

• C²H⁴O

• C₂H₄O

• 2C₄H₁O

Aluminum ions have a charge of 3+ and chloride ions have a charge of 1−.What is the formula of aluminum chloride?

• Al₂Cl₆

• AlCl₃

• AlCl

• Al₂Cl₃

Iron(III) ions have a charge of 3+ and oxide ions have a charge of 2−.What is the formula of iron(III) oxide?

• • Fe₂O₃

• • Fe₄O₆

• • Fe₃O₂

• • FeO₃

What is the formula of aluminium oxide?

• • Al₂O₃

• • Al₂(OH)₃

• • Al₂O

• • Al(OH)₃

A magnesium atom has the chemical formula Mg.What is the chemical formula of the magnesium ion?

• • Mg²⁺

• • Mg(2+)

• • Mg⁺

• • Mg^–