(i) On the diagram above, draw a line to show the evolutionary path of the Sun from its present position on the main sequence to the final stage in its evolution.

(ii) Explain, by reference to the Chandrasekhar limit, why the final stage in the evolution of the Sun is the one you indicated in (a)(i).

(i) Show that the mass of star X is approximately 14 solar masses. (Assume that n=3.5 in the mass–luminosity relation.)

(ii) State the likely final stage of star X.

(i) any line from the sun to red giants (anywhere above and right of the sun) and then anticlockwise to white dwarfs (anywhere below and left of the sun);

(ii) after the planetary nebula stage/red giants stage;
the remnant mass/core mass of the star will be less than the Chandrasekhar limit (and so will end up as a white dwarf);

(i) \(\frac{{{M_X}}}{{{M_ \odot }}} = {\left[ {\frac{{{L_X}}}{{{L_ \odot }}}} \right]^{\frac{1}{{3.5}}}}\);
\(\frac{{{M_X}}}{{{M_ \odot }}} = \left( {{{10}^{\frac{4}{{3.5}}}} = } \right)13.9\);

Evidence of calculation required for second mark (i.e. 3 sf or more showing).
Award [2 max] for valid alternative route to this answer.

(ii) neutron star / black hole;