Grade 11 Physical Science 2019 Paper 2

The balanced chemical equation for the EXTRACTION of gold from its ore is as follows: 10.1 State ONE disadvantage of using cyanide (CN– ) in the extraction of gold. (1) 10.2 Will the final solution of the extraction process be ACIDIC or BASIC (ALKALINE)? Give a reason for the answer. (2) 10.3 Determine the oxidation … Read more

The unbalanced equations for two redox reactions, in which SO2 is involved, are shown below. 9.1 Explain what is meant by the term redox reaction. (2) 9.2 Write down the oxidation number of Mn in: 9.2.1 KMnO4 (1) 9.2.2 MnSO4 (1) 9.3 Is Mn in Reaction 2 OXIDISED or REDUCED? Give a reason for the … Read more

8.1 Consider the balanced equations for the reaction of water with nitric acid and ammonia below 8.1.1 Define an acid in terms of the Lowry-Brønsted theory. (2) 8.1.2 Write down the FORMULA of ONE conjugate acid-base pair in Reaction 1. (2) 8.1.3 Is the solution formed in Reaction 1 ACIDIC or BASIC (ALKALINE)? Give a … Read more

The balanced equation for the reaction of carbon with steam is as follows: C(s) + H2O(g) → CO(g) + H2(g) The graph below, NOT drawn to scale, represents the change in potential energy ofthe substances during the reaction. 7.1 Define the term heat of reaction. (2) 7.2 Is the reaction ENDOTHERMIC or EXOTHERMIC? Give a … Read more

6.1 Potassium permanganate, KMnO4, burns with a bright flame when a few drops of glycerine are added to it. The incomplete equation for the reaction is: 6.1.1 Define the term molar mass. (2) 6.1.2 The composition of glycerine is as follows: 39,13% carbon; 8,7% hydrogen; 52,17% oxygen Determine the EMPIRICAL formula of glycerine. Show ALL … Read more

An unknown mass of gas is sealed in container M. The temperature is increased andthe pressure inside the container is measured.The experiment is now repeated using the same mass of the same gas in a differentcontainer, N.The results obtained are represented in the sketch graph below. 5.1 Determine the value of X as shown on … Read more

The melting points and boiling points of four substances (A, B, C and D) are shown inthe table below. 3.1 Define the term melting point. (2) 3.2 Explain the difference in melting points of HF and HCℓ by referring to theTYPE of intermolecular forces. (4) 3.3 Which ONE of the substances (A, B, C or … Read more