Chemistry: The Periodic Table Group 1

Which of the following metals react violently with water?

• Aluminium

• Potassium

• Iron

• Zinc

Strontium is in the same group as calcium. Which of the following statements is true?

• Each strontium atom loses 1 valence electrons during ionic bonding.

• Aqueous strontium hydroxide is acidic

• Strontium has a larger atomic radius than calcium.

• The chemical formula of strontium oxide is Sr₂O

Answer explanation

Strontium has one more filled electron shell than calcium, and hence has a greater atomic radius

A piece of sodium metal is dropped into water.

Which of the following observations is FALSE?

• Sodium hydroxide is formed.

• Hydrogen gas is formed.

• The resulting mixture turns red litmus paper blue.

• Sodium sinks to the bottom of the water.

A freshly cut piece of silvery sodium turns dull grey very quickly because

• it rusts in the presence of oxygen and water vapour in air.

• the knife is not clean.

• sodium forms compounds that are insoluble in water.

• sodium is oxidised by oxygen in air.

Which Group 1 metal has 4 electron shells?

Down Group 1, atomic radius increases. Hence, the electrostatic attraction between the positive nucleus and valence electron __________________.

Caesium is more metallic than lithium because

• caesium atoms loses its valence electron more readily

• it is less reactive than lithium

• it tarnishes in air quicker

• it is shinier

Group 1 elements are also called alkali metals because

• the metals are are alkalis

• the metals react with water to form alkalis

• the metals are not acidic

• the metals neutralise alkalis

Across a period, atomic size decreases because

• the electrostatic attraction between the positive nucleus and shells of electrons increases

• the number of electron shells decreases

• the number of electrons decreases

• the mass number increases

Sodium reacts with water violently. After the reaction, green universal indicator is added into the solution in the beaker. The mixture

• turns red

• turns yellow

• stays green

• turns purple