list any two observations when ferrous sulphate is heated in a dry test tube

list any two observations when ferrous sulphate is heated in a dry test tube

Aditya Raj Anand

Sunday, 1 August 2021

Chemistry

list any two observations when ferrous sulphate is heated in a dry test tube.

To answer this question, let's understand first the meaning of dry test tube.

As you can see in above figure. There are are four test tube. If we call it a dry test tube then it means a test tube with the ability to maintain or obsessed a heat. In other words a dry test tube is suddenly heating and then Cooling.

If you didn't understand it yet. Then just remember that the meaning of a dry test tube is like a simple and normal test tube having nothing in it. Even a micron atoms and molecules of any substance.

Now, let's come to our main question. The question said that, we have to write at least two observations that we Shaw when we heated ferrous sulphate in a dry test tube.

Answer:- These are following two observations that we observed when we heated ferrous sulphate in a dry test tube.

1. When we start heating ferrous sulphate (feso4) in a dry test tube changing of color takes place. Means the initial color stage of a ferrous sulphate compound is light green. But when we heated it for some time the color of the compound became brown.
2. When we heated ferrous sulphate then some evolution of gas takes place. Like sulphur dioxide, sulphur trioxide, etc. Due to the evolution of gas the ferrous sulphate compound smells odour like something burnt very badly.

When ferrous sulphate ($\text{FeSO}_4 \cdot 7\text{H}_2\text{O}$) is heated in a dry test tube, the following two observations can be made:

1. Loss of Water of Crystallization:

   • The green crystals of ferrous sulphate lose their water of crystallization and turn into a white solid.
   • Reaction: $$\text{FeSO}_4 \cdot 7\text{H}_2\text{O} \xrightarrow{\text{heat}} \text{FeSO}_4 + 7\text{H}_2\text{O}$$

2. Decomposition and Release of Gases:

   • On further heating, the anhydrous ferrous sulphate decomposes to produce ferric oxide ($\text{Fe}_2\text{O}_3$), sulfur dioxide ($\text{SO}_2$), and sulfur trioxide ($\text{SO}_3$).
   • This results in the evolution of pungent-smelling gases ($\text{SO}_2$ and $\text{SO}_3$).
   • Reaction: $$2\text{FeSO}_4 \xrightarrow{\text{heat}} \text{Fe}_2\text{O}_3 + \text{SO}_2 + \text{SO}_3$$

Observations Summary:

1. The green crystals turn white due to loss of water.
2. Pungent-smelling gases ($\text{SO}_2$ and $\text{SO}_3$) are evolved.