Learn It Sheets

• What is the product of a metal reacting with oxygen?


  Metal oxide
• What does oxidation mean in terms of electrons?


  Gain of oxygen or loss of electrons
• What does reduction mean in terms of electrons?


  Loss of oxygen or gain of electrons
• What is the order of reactivity of metals in the reactivity series?


  • Potassium (most reactive)
  • Sodium
  • Lithium
  • Calcium
  • Magnesium
  • Aluminium
  • Carbon
  • Zinc
  • Iron
  • Tin
  • Lead
  • Hydrogen
  • Copper
  • Silver
  • Gold (least reactive)
• Which metals react with cold water?

  Potassium, sodium, lithium, and calcium
• What is produced when a reactive metal reacts with water?


  Metal hydroxide and hydrogen gas
• Write the equation for sodium reacting with water.

  $2 \text{Na}(s) +$$2 \text{H}_2\text{O}(l) \rightarrow 2 \text{NaOH}(aq) +$$\text{H}_2(g)$
• How can we test for metal hydroxide?


  It turns universal indicator purple
• How can we test for hydrogen gas?


  It burns with a squeaky pop
• Describe the observations when alkali metals react with water.


  • Alkali metals float and move on the surface
  • They fizz and bubble (effervesce)
  • Calcium sinks and fizzes
  • Metals get smaller/disappear, producing a colorless solution
  • Sodium and potassium melt into spheres
  • Potassium catches fire with a lilac flame
• Describe the reactions of metals with acid.


  • Metal + acid → salt + hydrogen gas
  • Fizzing/bubbling occurs due to gas production
  • Metals get smaller/disappear, producing a colorless solution
  • Temperature increases (exothermic reaction)
• What pH do salts have?


  pH 7
• How do you name a salt?

  First part is the metal or ammonium, second part comes from the acid
• What type of salt is produced from hydrochloric acid?

  Chloride
• What acid is used to make a sulfate salt?

  Sulfuric acid
• What type of salt is produced from nitric acid?

  Nitrate
• What is the salt produced from hydrochloric acid and magnesium?


  Magnesium chloride
• What is the salt produced from ammonia and sulfuric acid?


  Ammonium sulfate
• What acid is used to make calcium nitrate?


  Nitric acid
• What determines how easily a metal reacts?


  How easily it loses its outer electron(s) to form a positive ion
• What is a displacement reaction?


  When a more reactive metal displaces a less reactive metal from a compound
• Are displacement reactions endothermic or exothermic?


  Exothermic
• How do you write ionic equations for displacement reactions?


  Only include species that actually react and remove spectator ions
• Write the word equation for iron reacting with copper sulfate.


  Iron + copper sulfate → copper + iron sulfate
• Write the ionic equation for the same reaction.


  $\text{Fe} +$$\text{Cu}^{2+} \rightarrow \text{Cu} +$$\text{Fe}^{2+}$
• What is a half equation?


  It shows what happens to just one species in a reaction
• Write the half equation for iron being oxidized.


  $\text{Fe} \rightarrow \text{Fe}^{2+} +$$2e^{-}$
• Write the half equation for copper being reduced.

  $\text{Cu}^{2+} +$$2e^{-} \rightarrow \text{Cu}$
• Which metals do not need to be extracted and why?


  Platinum, silver, and gold because they are unreactive
• Why do most metals need to be extracted?


  They are found as compounds in metal ores
• What is a metal ore?


  A mineral that contains enough metal for it to be cost-effective to extract
• How are metals less reactive than carbon extracted?


  By reduction using carbon
• What ions do all acids produce?


  Hydrogen ions, H+
• What ions do alkalis produce?


  Hydroxide ions, OH-
• Describe the pH scale and the color changes of universal indicator.


  • Strong acids (pH 0-2): red
  • Weak acids (pH 3-6): yellow/orange
  • Neutral (pH 7): green
  • Weak alkali (pH 8-11): blue
  • Strong alkali (pH 12-14): purple
• Name some strong acids.

  Hydrochloric acid, sulfuric acid, nitric acid
• Name some weak acids.

  Citric acid, ethanoic acid
• What is a strong acid?


  It fully ionizes in solution
• What is a weak acid?


  It partially ionizes in solution
• How do concentrated and dilute acids differ?


  Concentrated acids have a large amount of acid dissolved per unit volume