Question
This question is about solids, liquids and gases.
(a) The list gives the names of nine substances which are solids at room temperature.
a ceramic
aluminum
anhydrous cobalt(II) chloride
anhydrous copper(II) sulfate
calcium oxide
graphite
iodine
iron
sodium
Answer the following questions about these substances.
Each substance may be used once, more than once or not at all.
State which substance:
(i) turns pink when water is added to it[1]
(ii) is a non-metal which is used as a lubricant[1]
(iii) is used to neutralize acidic industrial waste[1]
(iv) is extracted from bauxite[1]
(v) is used as an electrical insulator.[1]
(b) Some changes of state of sodium are shown.
(i) State the names of the changes of state represented by A and B.[2]
A
B
(ii) Use the kinetic particle model to describe the arrangement and separation of the particles in:
solid sodium
liquid sodium [4][Total: 11]
Answer/Explanation
Ans:
(a)(i) (anhydrous) cobalt chloride
(a)(ii) graphite
(a)(iii) calcium oxide
(a)(iv) aluminum
(a)(v) ceramic
(b)(i) A: melting (1)
B: condensing / condensation (1)
(b)(ii) solid:
particles arranged regularly / particles ordered (1)
particles touching / particles close together (1)
liquid:
particles arranged irregularly / particles randomly arranged (1)
particles close together / particles touching (1)
Question
Matter can exist as solid, liquid or gas. The arrows show some changes of state
(a) Name the changes of state represented on the diagram.
(i) A ………………………………………………………………………………………………………………….. [1]
(ii) B ………………………………………………………………………………………………………………….. [1]
(iii) C ………………………………………………………………………………………………………………….. [1]
(b) Explain why energy has to be supplied to turn a liquid into a gas. ……………………………………………………………………………………………………………………………. [1]
(c) The diagrams represent the same number of particles of a gas in two containers, D and E, which have different volumes. The two containers are at the same temperature.
In which container will the pressure be higher? Explain your answer. [1] [Total: 5]
▶️Answer/Explanation
Ans:
2(a)(i) melt(ing)
2(a)(ii) sublimation / sublime
2(a)(iii) condensing/ condensation
2(b) overcome / break the attractive forces
2(c) E AND particles hit the walls (of the container) more often
Question
A student measures the maximum temperature changes when five different solids, P, Q, R, S and T,
are dissolved separately in water. She uses the apparatus shown below.
(a) The student stirs the mixture as each solid is added.
Suggest why she does this.
(b) Suggest two factors which should be kept the same to make the experiment a fair test.
1. ………………………………………………………………………………………………………………………………
2. …………………………………………………………………………………………………………………………
(c) The table of results is shown below.
(i) Which solid gave the greatest temperature change when dissolved in water?
(ii) Which solids gave an endothermic energy change when dissolved in water?
……………………………………………………… and ……………………………………………………….
(d) Radioactive isotopes can be used as a source of energy.
(i) Which one of the following isotopes is a radioactive isotope?
Put a ring around the correct answer.
(ii) An isotope of radium, Ra, has 226 nucleons in its nucleus.
How many neutrons does this isotope contain?
Use your Periodic Table.
(iii) Give one use of radioactive isotopes in medicine.
(e) Fractions obtained from the distillation of petroleum are also sources of energy.
(i) Which one of the following fractions is used as a fuel for jet aircraft?
Put a ring around the correct answer.
bitumen gasoline kerosene naphtha
(ii) Heptadecane, \(C_{17}H_{36}\), is present in the fuel oil fraction.
Complete the equation for the cracking of heptadecane to form two hydrocarbons.
\(C_{17}H_{36} → C_{12}H_{26} + ………………..\)
Answer/Explanation
Answer:
(a) make sure temperature change is the same throughout / make sure that there are no hot spots / no local heating;
(b) any two from:
• same amount of solid / same mass of solid;
• same volume of water;
• same amount of stirring;
(c) (i) Q
(ii) R; T;
(d) (i) \(^{235}U\)’;
(ii) 138;
(iii) cancer treatment/ tracer/ test thyroid function;
(e) (i) kerosene;
(ii) \(C_5H_{10}\);