transition metals.

Question

1) Magnesium is an s-block element, and the other three metals are d-block elements. What does this classification tell us about the electronic configuration of these elements?

2)  How do the compounds of transition metals compare to compounds of the s-block elements?

3) Why is there no change with the magnesium reaction  mixture when excess ammonia solution is added?

Answer 1

1) When an element is located in the s-block, the outermost electrons of that element are located in the s-orbital. Magnesium is is the 3rd period and 2nd group of the period table, and therefore its electronic configuration is 1s²2s²2p²3s^2.

The outermost electrons of transition metals, located in the d-block, occupy the d-orbital.

The difference in electronic configuration between Magnesium and transition metals affects the elements' chemical and physical properties.

2) Because transition metals have electrons that occupy the d-orbital, they often have multiple oxidation states. For example, Iron exists in +2 and +3 oxidation states.

Metals in the s-block generally exhibit only one oxidation state, typically corresponding to their group number. For example, sodium usually only has an oxidation state of +1.

3) Ammonia is a weak base and therefore does not induce a redox reaction with magnesium.