C5

• How do metal oxides form?

  Metals react with oxygen during oxidation
• What is reduction?


  Loss of oxygen

  Gain of electrons
• What is Oxidation?


  Gain of oxygen

  Loss of electrons
• What happens to metals when they react with other substances?

  Metal atoms form positive ions
• What is the reactivity of a metal determined by?

  Their tendency to make positive ions
• List metals in order of reactivity

  Potassium

  Sodium

  Lithium

  Calcium

  Magnesium

  Zinc

  Iron

  Copper
• Which two non-metals are included in the reactivity series?

  Hydrogen and Carbon
• How can metals less reactive than carbon be extracted from their oxides?

  Reduction with Carbon
• What is typically made when an acid reacts with some metals?

  Salts and Hydrogen
• How can acids be neutralised?

  Adding it to an alkali
• What is the general word equation for a metal reacting with an acid

  Metal + Acid > Salt + Water
• What is an example of an alkali?

  Soluble metal hydroxides
• What is an example of a base?

  Insoluble metal hydroxides and metal oxides
• What is the general word equation for a metal hydroxide reacting with an acid

  Metal Oxides + Acid > Salt + Water
• What is the general word equation for a metal carbonate reacting with an acid?

  Metal carbonate + acid -> salt + water + carbon dioxide
• What type of salt does hydrochloric acid produce?

  Chloride salt
• What type of salt does sulphuric acid produce

  Sulphate
• What type of salt does nitric acid produce?


  Nitrate
• How can a soluble salt be made?

  Add acid in excess to an insoluble substance such as metal, metal oxide, carbonate or hydroxide and filter off the excess. Crystallise the salt solution made
• What types of ions do acids produce in a solution

  $H^+$
• What types of ions do Alkalis produce in a solution

  $OH^-$
• What is the pH scale?

  A scale from 0 to 14 that is a measure of potential hydrogen in a solution
• What can be used to measure pH?

  pH meter, pH paper, pH indicator solution
• What is pH 7?

  Neutral solution
• What is pH less than 7?

  Acidic solution
• What is pH more than 7?

  Alkali solution
• What happens during a neutralisation reaction?

  Hydrogen ions react with Hydroxide ions to make water
• Write an equation to represent neutralisation reaction

  $H^+$$(aq) +$$OH^- (aq) -> H2O (l)$
• What is the conservation of energy principle?

  Energy is conserved in chemical reactions.
• How does the conservation of energy principle apply to chemical reactions?

  The amount of energy in the universe remains the same before and after a chemical reaction.
• What is an exothermic reaction?

  A reaction that transfers energy to the surroundings, increasing their temperature.
• Can you give examples of exothermic reactions?

  Combustion, oxidation reactions, and neutralisation reactions.
• What is the sign of energy change in an exothermic reaction?

  Negative sign of energy change.
• What is an endothermic reaction?

  A reaction that takes in energy from the surroundings, decreasing their temperature.
• Can you give examples of endothermic reactions?

  Thermal decomposition and the reaction of citric acid with sodium hydrogencarbonate.
• What is the sign of energy change in an endothermic reaction?

  Positive sign of energy change.
• What is activation energy?

  The minimum amount of energy that particles need to react.
• What is a reaction profile?

  A graph showing the relative energies of reactants and products, as well as activation energy.
• What occurs in a chemical reaction in terms of bond energies?

  Energy is supplied to break bonds and released when bonds are made.
• How do exothermic reactions relate to bond breaking and forming?

  Energy released from forming bonds is greater than that needed to break them.