Practical Chemistry · Chemistry · WB JEE
MCQ (Single Correct Answer)
1
Which one of the following cations gives a chocolate brown precipitate upon addition of aqueous solution of $\mathrm{K}_4\left[\mathrm{Fe}(\mathrm{CN})_6\right]$ ？
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2
Kjeldahl's method cannot be used for the estimation of nitrogen in which compound?
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3
The compound that does not give positive test for nitrogen in Lassaigne's test is
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4
To a solution of a colourless efflorescent sodium salt, when dilute acid is added, a colourless gas is evolved along with formation of a white precipitate. Acidified dichromate solution turns green, when the colourless gas is passed through it. The sodium salt is
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5
Compound X is tested and the results are shown in the table.
Which ions are present in compound 'X'?
| Test | Result |
|---|---|
| Aqueous sodium hydroxide is added, then heated gently. Dilute hydrochloric acid is added. |
Gas given off which turns damp red litmus paper blue. Effervescence, gas given off which turns lime water milky and acidified $${K_2}C{r_2}{O_7}$$ paper green. |
Which ions are present in compound 'X'?
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