28a)

When magnesium metal is added to an alloy made from copper and chromium there is a resultant improvement on the alloys mechanical and electrical properties.

i. Write the ground state electron configuration of the Mg atom and state how many valence electrons are present. (1 mark)

ii. Explain why Magnesium is placed in Period 3 of the Periodic table. (1 mark)

iii. Write the ground state electron configuration of the Cr atom and Cr²⁺ atom (2 marks)