Predicting chemical reactions

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Question 23
Medium

Potassium is in Group 1 of the Periodic Table.

a.

Potassium reacts with water to make potassium hydroxide, KOH\text{KOH}KOH, and hydrogen.

Write the balanced symbol equation for the reaction between potassium and water.

[2]
b.

Potassium ions, K+\text{K}^+K+, are formed when potassium reacts with water.

Look at the equation. It shows how a potassium ion is formed from a potassium atom: K−e−→K+\text{K} - \text{e}^- \rightarrow \text{K}^+K−e−→K+ The symbol e−\text{e}^-e−, means an electron.

The formation of a potassium ion from a potassium atom is an example of oxidation.

Explain why.

[1]
c.

Caesium is another element in Group 1.

Caesium reacts much faster than potassium does.

Explain why. Use ideas about electrons in your answer.

[3]

Predicting chemical reactions Questions

  1. GCSE
  2. /Chemistry
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