If you add carbon disulphide in a test-tube containing a mixture of iron filings and sulphur powder, what do you observe after shaking the test-tube well ? (a) Sulphur dissolves to form colourless solution and the iron filings settle down. (b) Some brown gas is evolved. (c) Yellow solution is formed and iron filings settles down. (d) After some time, carbon disulphide, sulphur and iron filings form three separate layers in the test-tube.
CBSE Class IX Science VSA (1 Mark)
Answers
On adding carbon disulphide in a test-tube containing a mixture of iron filings and sulphur powder, and shaking it well, it is observed that a yellow coloured solution is formed and the iron fillings settle down in the bottom of the test tube, i.e., option (C) is correct.
• Iron fillings are small, solid pieces of iron, and sulphur powder is a yellow coloured powder.
• Carbon disuplhide is a colourless liquid, which on adding to the mixture of sulphur and iron fillings, causes the sulphur powder to disperse in it, thereby forming a yellow coloured colloidal solution of sulphur and carbon disulphide. Iron fillings remain unreacted with CS2, and being solid in nature, settle down in the test tube. Therefore,
CS2 + S + Fe fillings → Yellow solution of CS2 and S + Fe fillings
Hence, option (C) is correct.
Here are the observations when carbon disulphide is added in a test-tube containing a mixture of iron filings and sulphur powder:
Explanation:
The correct answer to this question is option c! We can see that a yellow colour solution is prepared on mixing the above mentioned ingredients and on shaking it properly.
All the iron fillings will settle down at the bottom of the test tube as they are insoluble. However, these can be separated with the help of filtration. We can obtain the solid sulphur powder when the solution is evaporated.