2018
Question 11
Given the digits: 3 ; 4 ; 5 ; 6 ; 7 ; 8 and 9 11.1 Calculate how many unique 5-digit codes can be formed using the digits above, if: 11.1.1) The digits may be repeated (2) 11.1.2) The digits may not bc repeated (2) 11.2 How many unique 3-digit codes can be formed … Read more
Question 10
In the flow diagram below, I and II represent industrial processes used in the fertiliser industry. P and Q are chemical reactions that take place to produce ammonium sulphate and fertiliser Y respectively. 10.1 Write down the name of the industrial process: 10.1.1 I (1) 10.1.2 II (1) 10.2 Write down the NAME or FORMULA … Read more
Question 9
The electrolytic cell below is set up to obtain pure copper from a piece of impure copper. The impure copper contains other metals, such as platinum, iron, cobalt, silver and nickel. The cell potential of the power source is adjusted so that only copper is deposited on electrode B. 9.1 Define an electrolytic cell. (2) … Read more