Standard Grade Revision Units 1 and 2. Q.1 When green copper carbonate is added to hydrochloric acid solution a rapid reaction takes place in which a gas is given off and a blue solution is formed. Give two pieces of information which would prove that a chemical reaction had taken place. Answer:- 1) In the reaction a gas is formed. 2) In the reaction there is a colour change – the green copper carbonate changes to a blue solution.. Standard Grade Chemistry

Units 1 and 2 Revision Q2. When silvery magnesium ribbon is burned in air the magnesium combines with oxygen in the air to form white magnesium oxide. In the reaction heat and light energy are given out. (a)Give two pieces of information that shows that a chemical reaction has taken place. (b)What word is used to describe a reaction in which energy is given out? (c)Write a word equation for the reaction. Answers:- (a)1. Colour change (Silver magnesium to white powder). 2. Energy given out. (b) Exothermic. (c) Magnesium + Oxygen  Magnesium oxide Burning magnesium in air

Q3. Barium chloride and sodium sulphate solutions are both colourless. When the two solutions are mixed a white solid called barium sulphate is formed. (a) Give one piece of information which shows that a chemical reaction had taken place. (b) Which of the chemicals mentioned is the precipitate? Units 1 and 2 Revision Answers:- (a) Solid being formed in the reaction when the chemicals present in the two solutions react together. (b) The barium sulphate is the precipitate. A precipitate is an insoluble solid formed when two solutions are mixed. Mixing solutions of barium chloride and sodium sulphate

Units 1 and 2 Revision. Q4. Write the symbol for each of the following elements. (a) Potassium(b) Phosphorus(c) Sulphur (d) Sodium(e) Calcium(f) Copper Answers:- (a) K(b) P(c) S (d) Na(e) Ca(f) Cu Q5. What are the names of the elements whose symbols are shown below? (a) Zn(b) O(c) F (d) He(e) Fe(f) Cr Answers:- (a) Zinc(b) Oxygen(c) Fluorine (d) Helium(e) Iron(f) Chromium Use your data booklet.

Units 1 and 2 Revision. Q6. Name the elements present in the following compounds. (a) Lead sulphide(b) Calcium carbide (c) Copper sulphate(d) Sodium hydrogencarbonate. Answers:- (a)Lead and sulphur (b) Calcium and carbon (c) Copper, sulphur and oxygen (d) Sodium, hydrogen, carbon and oxygen Q7. Name the compounds which contain the following elements. (a) Oxygen and iron. (b) Barium, oxygen and carbon (c) Lead, nitrogen and oxygen (d) Chlorine and copper. Answers:- (a) Iron oxide(b) Barium carbonate (c) Lead nitrate(d) Copper chloride Standard Grade Chemistry

Q8. Use the word box below to answer the following solutesolutionsolvent diluteconcentratedsaturated (a) When sodium chloride is dissolved in water the water is described as being the ………………… (b) When sodium chloride is dissolved in water the sodium chloride is described as being the …………………. (c) When no more sodium chloride will dissolve in water the sodium chloride solution is said to be …………………… (d) A solution which contains a lot of sodium chloride dissolved in a small volume of water is said to be ………………………… Units 1 and 2 Revision. Answers:- (a) solute (b) solvent(c) saturated (d) concentrated Standard Grade Chemistry

Units 1 and 2 Revision. Q9. (a) Identify the two experiments which can be used to investigate the effect of concentration on the rate of the reaction. (b) Identify the experiment with the fastest reaction rate. Answers (a)C and D. (b) F Standard Grade Chemistry

Units 1 and 2 Revision. Q10. Matthew added manganese dioxide to hydrogen peroxide solution, oxygen was produced. Manganese dioxide is a catalyst. (a) What is the purpose of a catalyst? (b) What will be the mass of the manganese dioxide at the end of the reaction? (c) What would happen to the rate at which oxygen gas is given off if the temperature was raised to 35 o C? Answers: (a) A catalyst speeds up a reaction. (b) 0.1 g (A catalyst is not used up in a reaction). (c) The rate of oxygen gas production will increase. Standard Grade Chemistry

Units 1 and 2 Revision. Q11. Zinc reacts with dilute sulphuric acid. Identify the two factor which will speed up the reaction. AUsing a larger volume of acid BDiluting the acid with water CUsing a larger beaker DHeating the acid EUsing a catalyst Answers:- D and E. Standard Grade Chemistry

Units 1 and 2 Revision. Complete the following sentences. 1.All chemical reactions involve the formation of one, or more ……………… substances. 2.Everything in the world is made from about ……………. elements. 3.When elements join together they form ………………………….. 4.A mixture is formed when two, or more, substances come together but do …… react. new 100 compounds not Standard Grade Chemistry

Units 1 and 2 Revision. Complete the following sentences. 1.………………. the temperature will speed up a reaction. 2.Changing from a lump to a powder increases the ………………. ………………. of a solid and ………….. ………… a reaction. 3.2 mol/l acid is ……………. concentrated than 1 mol/l acid. The more concentrated acid reacts more ………………… with marble chips than the dilute acid. surface area speeds up more quickly Increasing Standard Grade Chemistry