Question

33. An element X which is a yellow solid at room temperature shows catenation
and allotropy. X forms two oxides which are also formed during the thermal
decomposition of ferrous sulphate crystals and major air pollutants.
1) Identify the element X
2) Write the electronic configuration of X.
3) Write the balanced chemical equation for the thermal decomposition of ferrous
sulphate crystals
4) What would the nature of the oxides formed?
5) Locate the position of element in the periodic table.​

Answer 1

Answer:

1. lead oxide

2. atomic no. is 82 too big it will not come in exam

3. 2feso4-fe2o3+so2+so3

4. solid

5. group no. 14 and period 6

all the best for ur exam!!!

Answer 2

1) An element 'X' is yellow in colour and is solid at room temperature. It also shows catenation and allotropy property

Catenation: Self linking property of an element to form large chains and rings.

Allotropy: Different forms of the same element.

X forms two oxides which are also formed during the thermal decomposition of ferrous sulphate crystals and major air pollutants.

$\sf \: FeSO_4 \:\underrightarrow{\sf \triangle} \: Fe_2O_3+SO_2+SO_3$

From the above relation, it is confirmed that the element 'X' is Sulphur.

As it's colour is yellow and it is solid at room temperature. Also, shows catenation and allotropy property.

Also, it forms two oxides i.e. $\sf{SO_2}$ and $\sf{SO_3}$ which are air pollutants by thermal decomposition of ferrous sulphate crystals.

2) Atomic number of 'X' i.e. Sulphur is 16.

In K shell 2 electrons are present, in L shell 8 electrons are present and in M shell 6 electrons are present.

Electronic configuration of Sulphur = 2, 8, 6

3) Chemical equation for the thermal decomposition of ferrous sulphate crystals is:

$\sf \:FeSO_4 \:\underrightarrow{\sf \triangle} \: Fe_2O_3+SO_2+SO_3$

Balanced equation:

$\sf \:2FeSO_4 \:\underrightarrow{\sf \triangle} \: Fe_2O_3+SO_2+SO_3$

4) Sulphur is non-metal and non-metals shows acidic behaviour. Therefore, $\sf{SO_2}$ and $\sf{SO_3}$ are acidic in nature.

5) Atomic number of Suplhur is 16. Means, Group number is 16.

Also, it's electronic configuration is 2, 8, 6 which is filled in three shells K, L and M. Period number depends upon number of shell. In Sulphur three shells i.e. K, L and M are used. So, it's Period number is 3.