Uranium-238 is a naturally-occurring alpha emitter. It can be used in the manufacture of the isotope plutonium-239, during which it is bombarded by neutrons. The process of converting a nucleus…
Disproportionation is the simultaneous oxidation and reduction of the same species in areaction.In which of the following chemical equations does disproportionation occur?1 Fe + CuCl2 → FeCl2 + Cu2 Cu…
Dolly the sheep was born in 1996. She was unusual because she had no biological father. Sheep have a diploid number of 54 chromosomes in their body cells. The diagram…
In triangle PRS, line QT is parallel to side RS.RS = 1.5 cmTS = 1.8 cmQT = 0.3 cmWhat is the length of PS? Answer: 12) F To solve this…
Two resistors R1 and R2 are connected in series with a cell. Resistor R1 has twice the resistance of resistor R 2. Six statements about this circuit are given below.1…
A piece of magnesium ribbon is dropped into a beaker of dilute aqueous hydrochloric acid at room temperature. After a while the production of bubbles of gas slows down. Which…
The diagram shows four experiments used to investigate movement of substances across dialysis tubing. This tubing is a partially permeable membrane which allows both glucose and water to pass through…
In a group of 20 patients at a medical centre, 5 suffered from migraines. Two patients from the group of 20 were picked at random for a survey on the…
A puddle is left on a road after a rain shower. The water in the puddle slowly disappears by evaporation. Three statements about the effect of changing different conditions on…
Which of the following atoms and ions contain(s) 20 neutrons and 18 electrons? 1 –23416 S2 –lC37173 Ar40184 +K39195 Ca Answer: 6) D Remember mass number = no. of protons…