Reactivity and Extraction

• How do metals react with water and acids?

  They react differently based on reactivity.
• What do highly reactive metals produce when reacting with water?

  Hydrogen gas and metal hydroxide
• Which metals are considered highly reactive?

  Potassium, sodium, lithium, calcium
• How do less reactive metals like magnesium behave with water?

  They react slowly with water.
• Which metals do not react with water at all?

  Copper, silver, gold
• What do reactive metals form when they react with dilute acids?

  A salt and hydrogen gas
• What is the reaction of magnesium with hydrochloric acid?

  Magnesium chloride and hydrogen gas
• What happens when zinc reacts with sulfuric acid?

  Zinc sulfate and hydrogen gas are produced
• Which metals do not react with dilute acids?

  Copper, silver, gold
• What occurs during displacement reactions?

  A more reactive metal displaces a less reactive metal
• What do more reactive metals do to metal oxides when heated?

  Reduce metal oxides to form free metal
• What is the reactivity series of metals based on their reactions with water and acids?

  Potassium > Sodium > Lithium > Calcium > Magnesium > Aluminium > Zinc > Iron > Copper > Silver > Gold
• Why do highly reactive metals like potassium, sodium, and lithium react vigorously with water?

  They produce hydrogen gas and metal hydroxide when reacting with water
• What is the reaction between magnesium and hydrochloric acid?

  Magnesium + hydrochloric acid → magnesium chloride + hydrogen
• Why do less reactive metals like copper, silver, and gold not react with dilute acids?

  They are not reactive enough to displace hydrogen from the acid
• What is the reaction between magnesium and copper(II) oxide?

  Magnesium + copper(II) oxide → magnesium oxide + copper
• What is the reaction between zinc and copper sulfate solution?

  Zinc + copper sulfate → zinc sulfate + copper
• What are the conditions required for iron to rust?

  Presence of water, presence of oxygen, and presence of salt (e.g. NaCl)
• How does galvanizing protect iron from rusting?

  Coating iron with zinc, which acts as a sacrificial metal and corrodes instead of the iron
• What is the definition of oxidation?

  Gain of oxygen or loss of electrons
• What is the definition of reduction?

  Loss of oxygen or gain of electrons
• What is the role of an oxidizing agent in a redox reaction?

  It causes oxidation by accepting electrons
• What is the reaction between magnesium and copper sulfate?

  Magnesium + copper sulfate → magnesium sulfate + copper
• Which metal reacts the most rapidly with dilute hydrochloric or sulfuric acid?

  Magnesium
• Which metal does not react with dilute hydrochloric or sulfuric acid?

  Copper and silver
• What are the key differences between the reactivity of metals with water and dilute acids?

  • Highly reactive metals (e.g. K, Na, Li, Ca) react vigorously with water, producing hydrogen gas and metal hydroxide
  • Less reactive metals (e.g. Mg) react slowly with water
  • Unreactive metals (e.g. Cu, Ag, Au) do not react with water
  • Reactive metals (e.g. Mg, Zn, Fe) react with dilute acids to form a salt and hydrogen gas
  • Less reactive metals (e.g. Cu, Ag, Au) do not react with dilute acids
• What are the different methods for preventing the rusting of iron?

  • Barrier methods: Coating iron with paint, oil, or grease to prevent contact with water and oxygen
  • Galvanizing: Coating iron with zinc, which protects the iron by acting as a sacrificial metal
  • Sacrificial protection: Attaching a more reactive metal (e.g. Mg, Zn, Al) to iron, so the more reactive metal corrodes instead
• What are the key steps in the practical investigation of the reactions of metals with dilute acids?

  1. Add a small piece of metal (Mg, Zn, Fe) to a test tube containing dilute HCl or H2SO4
  2. Observe the reaction (fizzing, temperature change, formation of gas bubbles)
  3. Test the gas with a lighted splint - a "pop" sound confirms the presence of hydrogen
• What are the key observations and conclusions from the practical investigation of the reactions of metals with dilute acids?

  Observations:

  • Magnesium reacts rapidly, producing lots of bubbles (hydrogen)
  • Zinc reacts moderately
  • Iron reacts slowly
  • Copper and silver do not react

  
  

  Conclusions:

  • Reactivity decreases down the reactivity series
  • More reactive metals (Mg, Zn, Fe) react with acids to form a salt and hydrogen
  • Less reactive metals (Cu, Ag) do not react with dilute acids
• What are the key steps in a redox reaction?

  • Oxidation: Gain of oxygen or loss of electrons
  • Reduction: Loss of oxygen or gain of electrons
  • Redox reaction: Oxidation and reduction happen simultaneously
  • Oxidizing agent: Substance that causes oxidation by accepting electrons
  • Reducing agent: Substance that causes reduction by donating electrons
• What is the relationship between the reactivity series and displacement reactions?

  • Displacement reactions occur when a more reactive metal displaces a less reactive metal from its oxide or salt solution
  • More reactive metals can reduce metal oxides when heated, forming the free metal and an oxide of the more reactive metal
  • A more reactive metal can replace a less reactive metal from its salt solution
• What are the key trends in the reactivity series of metals?

  • Most reactive: Group 1 (K, Na, Li) and Group 2 (Ca) metals - react violently with water and acids
  • Middle-range: Mg, Zn, Fe - react moderately with water and acids
  • Least reactive: Cu, Ag, Au - do not react with water or dilute acids