The element lithium has several different isotopes.

1. (a)(i)State one way in which the compositions of the atoms of all lithium isotopes are the same.[1]
2. (a)(ii)State one way in which the composition of a lithium atom of one isotope is different from the composition of a lithium atom of a different isotope.[1]
3. (b)(i)Fig. 8.1 is a diagram that represents a neutral atom of a radioactive isotope of lithium (Li). There are three electrons in orbit around the nucleus. [Figure 8.1] The nuclide symbols for isotopes of lithium are represented as ^X_Y Li where X and Y are numbers. Determine the values of X and Y for the isotope represented by Fig. 8.1.[2]
4. (b)(ii)An ion of this isotope of lithium has a single positive charge and is represented as (Li+). Describe how the diagram that represents this ion differs from Fig. 8.1.[1]
5. (c)(i)Radioactive isotopes emit nuclear radiation which can affect living things. State one damaging effect of nuclear radiation.[1]
6. (c)(ii)The emission of radioactive radiation from an unstable isotope is described as random and spontaneous. State what is meant by 'random' and what is meant by 'spontaneous'.[2]

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