Chemistry 0620 · IGCSE · Isotopes

Isotopes — practice question

(a)[2]

What does the term isotopes mean?

(b(i))[1]

How many neutrons does this sulfide ion contain?

(b(ii))[1]

How is a sulfide ion, $\text{S}^{2-}$, made from a sulfur atom?

(b(iii))[1]

Which element forms a 2+ ion with the same number of electrons as a $\text{S}^{2-}$ ion?

(c)[5]

(i) Add the correct state symbols to complete stage 1.\nS(....) + O_2(....) → SO_2(....)\n(ii) Give the name of the catalyst used in stage 2 and state the temperature employed.\ncatalyst .................\ntemperature ................. ^{\circ}C\n(iii) Write the equations for the reactions in stage 3 and stage 4.

(d)[3]

(i) State one environmental reason for not allowing sulfur dioxide to be released into the atmosphere.\n(ii) Describe the test for sulfur dioxide.\nInclude both the test and the observations.

(e)[3]

Calculate the empirical formula for this compound.

Worked solution & mark scheme

This 16-mark question has a full step-by-step worked solution and mark scheme. One marking point: Atoms that have the same proton number

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