Chemistry ( multiple choice )

• In the reactivity series, reactivity goes up the group.
• 1. Potassium is a metal that is very high in the series
• Silver is found low in the reactivity series
• A metal that is high in the series almost certainly occurs naturally as a compound of the element.
• When iron is heated with lead oxide, iron oxide and a shiny ball of lead are formed. The iron has reduced the lead oxide.
• This metal (X) displaces copper from copper sulphate solution but does not displace zinc from zinc sulphate. From this we can tell that the order of reactivity (most reactive first) is zinc;X;copper.
• There would be no reaction if a sample of silver, gold or platinum is placed in acid
• 1. Displacement reaction is a chemical reaction where a more reactive metal takes the place of a less reactive metal in a compound
•   Lithium chloride + Iron ->Lithium chloride + Iron (No change)
• When scrap iron is added to blue copper sulphate solution, a pinky-brown deposit is formed and a pale green solution is left above it. The pale green solution is of iron sulfate.
• If the metal is more reactive than the metal in the compound it completes with the less reactive metal. Therefore, it can conclude that
•      When metals react with acid, they always produce salt and hydrogen
• acid + base ---> salt + water = neutralisation reaction
• Metal carbonates react with acid to form metal carbonate and hydrogen gas.
• Calcium carbonate + hydrochloric acid --> calcium chloride + carbon dioxide + water.
• Carbon dioxide is always produced when carbonates react with acids.
• Limewater turns white if it reacts with carbon dioxide.
• Hydrochloric acid + magnesium hydroxide -->Magnesium chloride + water
• Base, metal, carbonates : three types of reaction of acids.
• sodium hydrogen carbonate when added to acetic acid evolves a gas. It turns the limewater milky.
• Metal + acid ---> metal salt + hydrogen

  ( Metal salt and hydrogen )
• When sodium reacts with water, hydrogen gas is produced.
• A metals is reacting with water if it's fizzing.
• potassium hydroxide + phosphoric acid --> potassium phosphate
• When investigating the rate of reaction, we look at the speed of reaction.
• Increase in temperature of the reactants can increase collision between the particles thus increasing the rate.
• Products will form faster if concentration of the reactants is increased
• Catalyst is a substance that increases the rate of a reaction without being used up during the reaction.
• Smaller particle size allows for a larger surface area to be exposed for the reaction
• Increasing the temperature will increase the kinetic energy of particles, therefore increasing the collisions between particles
• A catalyst works by lowering the activation energy
• If the temperature is reduced, the reaction rate will decrease
• The faster the surface area of the reactants, the faster the reaction at
• Concentration refers to how much solute is dissolved in
• Why don't all collisions between particles cause a reaction?

  • . not all the particles collide with enough energy
• To slow down a chemical reaction, place the reactants in a cold bath.
• When surface area is decreased the rate of reaction decreases, because there are LESS possible sites for correct collisions