Light travels through glass at a speed which is 2/3 of its speed through air.Light travels through water at a speed which is 3/4 of its speed through air.A ray…

The gases X and Y react with each other to produce gas Z according to the equation: 2X(g) + Y(g) → 2Z(g) 100 cm3 of X was mixed with 10…

An experiment was carried out to investigate a gene for coat colour in mice. The diagram shows the results of three crosses between different mice, producing three different families, P,…

Some blood is found at a crime scene. The police know that it belongs to the one criminal involved. A person’s red blood cells can have type A antigens, type…

An object that has a weight of 15 N on Earth is taken to a planet where it has a weight of 3.0 N.The planet has no atmosphere. Which line…

Calcium carbonate reacts with hydrochloric acid. The reaction gives off carbon dioxide gas. Line X on the graph shows the volume of carbon dioxide formed against time when 100 cm3…

Which statements describe a role of mitosis?1 asexual reproduction2 growth of a cell3 repair of cells4 stem cell division Answer: 21) A 1 – mitosis does not involve a mate.…

Rearrange the formula = a/b=c/d+e/f e to make f the subject? Answer: 20) C a = c + eb d f Let us first solve the right hand side (RHS).…

A defibrillator provides an electric shock to a heart to restore its normal rhythm. The energy to do this is 125 J, at a steady voltage of 500 V, for…

What volume of a 0.10 mol dm–3 solution of NaOH is needed to neutralise 30 cm3 of a 0.20 mol dm–3 aqueous solution of a diprotic acid? Answer: 18) C…