(2 marks) (b) Figure 3 shows the apparatus used to burn hydrogen in air. II On addition of cleaned magnesium ribbon, it gives off a gas that burns with a pop sound.
The new exam has a focus on longer, more in depth, lab-based questions.
The penalty for incorrect answers on the multiple choice section was also removed.
III On addition of powered sodium carbonate, it gives off a gas which forms a precipitate with calcium hydroxide solution.
IV When warmed with copper(II) oxide powder, a blue solution is obtained but no gas is given of V On addition of aqueous barium chloride, a white precipitate is obtained.