IGCSE Combined science (Chemistry)

The apparatus used to remove sand from a mixture of salt and sand is shown. The contents of beaker 1 are stirred and then poured into the funnel above beaker 2. What is in beaker 2?

• a mixture of an element and a compound

• a mixture of two compounds

• one compound only

• one element only

Which row describes an element and a compound?

• A

• B

• C

• D

The positions of elements P, Q, R, S and T in the Periodic Table are shown. The letters are not the symbols for the elements.

Which element forms an ionic compound with element P?

• Q

• R

• S

• T

The diagram shows the apparatus used for the electrolysis of lead(II) bromide using inert electrodes X and Y. Lead is formed at electrode Y.

Which statement about the electrolysis is correct?

• A green gas is given off at electrode X.

• Electrode Y is the anode.

• Only a physical change takes place when a current is passed.

• The electrolyte is in the molten state.

Which temperature changes occur during exothermic and endothermic reactions?

• A

• B

• C

• D

What is a catalyst?

• a substance that decreases the rate of reaction and is chemically changed at the end of the reaction

• a substance that decreases the rate of reaction and is chemically unchanged at the end of the reaction

• a substance that increases the rate of reaction and is chemically changed at the end of the reaction

• a substance that increases the rate of reaction and is chemically unchanged at the end of the reaction

Which word equation represents the reaction of an acid with a carbonate?

• acid + carbonate → salt + carbon dioxide

• acid + carbonate → salt + carbon dioxide + water

• acid + carbonate → salt + hydrogen + water

• acid + carbonate → salt + water

The results of two tests on a solution of substance R are shown. What is R?

• iron(II) carbonate

• iron(III) carbonate

• iron(II) chloride

• iron(III) chloride

A soft metal reacts vigorously with cold water. What is the position of this metal in the Periodic Table?

• A

• B

• C

• D

W, X, Y and Z are four metals.

W forms a compound that is used to speed up chemical reactions.

X forms coloured compounds.

Y has a high melting point.

Z has a low density.

Which metals are transition elements?

• W, X and Y

• W and X only

• X, Y and Z

• Y and Z only