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…

SCID is an inherited condition in humans. People with some types of SCID are unable to make a functional enzyme necessary for the production of healthy white blood cells. A…

Which one of the following is equivalent to (√5 – 2)²? Answer: 4) F (√5 – 2)²Using the (a – b)² = (a² + b² – 2ab) rule, (√5)² +…

Below are four statements about electromagnetic waves.1 Microwaves have a smaller wavelength than visible light.2 The speed of visible light in a vacuum is higher than the speed of other…

The diagram shows an electrolysis experiment. Which reaction occurs at the anode and which reaction occurs at the cathode for this experiment? Answer: 2) E You must first know what…

The diagram shows a section through part of a healthy human. Which row in the table shows the correct secretions from P, Q and R? Answer: 1) A P is…