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प्रश्न
Dry raisins were soaked in water for 2 hours, to determine the percentage of water absorbed by raisins. Before final weighing of swollen raisins, the extra water left on the surface of soaked raisins was removed by:
विकल्प
Gently rubbing with cotton cloth
Hot air blower
Dry cotton wool
Filter paper
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उत्तर
Not in Current Syllabus
The raisins after being soaked in water are dried on a piece of filter paper in order to remove the excess water present on their surface.
The Correct Answer is D
संबंधित प्रश्न
When hydrogen is passed over copper oxide, copper and steam are formed. Write a balanced equation for this reaction and state which of the chemicals are non-metals.
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Barium chloride solution reacts with sodium sulphate solution to give insoluble barium sulphate and a solution of sodium chloride.
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PbO + NH3 → Pb + H2O + N2
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copper + nitric acid → copper nitrate + nitric oxide + water
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| Column A | Column B |
| (a) Blue salt changes to white and then black | (i) Ammonium dichromate |
| (b) Orange coloured compound changes to green. | (ii) Iodine |
| (c) Red compound changes to brown and then yellow. | (iii) Zinc Nitrate |
| (d) White to yellow when hot and white when cold. | (iv) Copper sulphate |
| (e) Violet solid changes to violet vapours. | (v) Red Lead |
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four product
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Fe2O3 + H2 → Fe + H2O
CaCO3 + 2HCl[dil.] → CaCl2 + H2O + CO2 [g]
State the information not conveyed by the above chemical equation.
