Metal Reactions with Water

Behavior of Metals

Physical Properties of Metals

• Learning objective: Understand the physical properties of metals.
• Learning objective: Understand the chemical properties of metals.

Chemical Properties of Metals with Distilled Water

Reactions with Cold Water

• Potassium (K) reacts rapidly with cold water.
  • $2K + 2H<em>2O \rightarrow 2KOH + H</em>2$
  • The reaction produces potassium hydroxide (KOH) and hydrogen gas (H₂).
  • The solution turns alkaline (red litmus paper turns blue).
  • The reaction is fast.
• Sodium (Na) reacts with cold water.
  • $2Na + 2H<em>2O \rightarrow 2NaOH + H</em>2$
  • The reaction produces sodium hydroxide (NaOH) and hydrogen gas (H₂).
  • The produced hydrogen gas ignites.
  • Observation: Bubbles, fizzing.
  • Turns the solution alkaline (red to blue).

Reactions with Hot Water

• Lithium (Li) reacts moderately with hot water.
  • $2Li + 2H<em>2O \rightarrow 2LiOH + H</em>2$
  • Observation: Fizzing, bubbles, effervescence.
• Calcium (Ca) reacts with hot water.
  • $Ca + 2H<em>2O \rightarrow Ca(OH)</em>2 + H_2$

Reactions with Steam

• Magnesium (Mg) reacts with steam.
  • $Mg + H<em>2O \rightarrow MgO + H</em>2$
  • Reaction is moderate.
• Iron (Fe) or Zinc (Zn) react slowly with steam.
  • $3Fe + 4H<em>2O \rightarrow Fe</em>3O<em>4 + 4H</em>2$

No Reaction

• Copper (Cu) does not react with water or steam.
  • No reaction is observed.
  • No fizzing or bubbles.
  • No effervescence.