Sec 3 Challenge 2

Which of the following would be found dissolved in the blood plasma of a human?

• Glucose, urea, and hormones

• Oxygen, urea, and starch

• Carbon dioxide, hormones, and haemoglobin

• Carbon dioxide, oxygen, and urea

Some chemical compounds are purified by recrystallisation.

What can be used to test the purity of the crystals?

• melting point

• colour of crystals

• size of crystals

• solubility

Why are passengers not allowed to stand up on the top deck of the double-decker bus?

• They cannot be trusted to stand where the driver can’t see them.

• They would raise the pressure exerted by the bus on the road.

• They would increase the gravitational potential energy of the bus.

• They would raise the centre of mass of the bus, causing it to become less stable.

Which of the following is a correct explanation of the effect of root hairs on absorption?

• Provide a large surface area, maximising the rate of absorption of water and ions by osmosis

• Provide a large surface area, maximising the rate of absorption of water by osmosis and ions by active transport

• Increase the surface area, maximising the uptake of water by osmosis and ions by diffusion

• Provide a surface area, increasing the rate of absorption of water and ions by active transport

What is the electronic structure of an atom with a proton number 5 and a nucleon number 11?

• 1,8,2

• 2,8,1

• 2,3

• 3,2

Which of the following energy sources produce no atmospheric pollution?

• Wave power, solar cells, and geothermal power

• Nuclear fuel, wave power, and solar cells

• Fossil fuels, biofuels, and nuclear fuel

• Biofuel, nuclear fuels and wave power

Which of the following orders would be correct showing the size of structure from biggest to smallest?

• Chromosome → red blood cell → stomach → gene → nucleus

• Stomach → red blood cell → gene → chromosome

• Stomach → red blood cell → nucleus → chromosome → gene

• Gene → chromosome → red blood cell → stomach

Strontium, Sr, is a metal that forms an ionic chloride SrCl2.

Sulphur, S, is a non-metal that forms a covalent chloride SCl2.

Which compound is likely to have the higher melting point (m.p.) and which is more soluble in water?

• A

• B

• C

• D

Which statement is true about evaporation?

• Evaporation takes place throughout the liquid.

• Evaporation accelerates as temperature decreases.

• Evaporation causes cooling.

• No change of temperature happens during evaporation.

The relative atomic mass of oxygen is 16 and that of hydrogen is 1.

This means that …(i)… of oxygen has the same mass as …(ii)… of hydrogen. Which words correctly complete the gaps?

• A

• B

• C

• D