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प्रश्न
When KOH solution is added to potassium dichromate solution the colour of solution
changes to yellow, because _______
(A) chromate ion changes to dichromate ion
(B) dichromate ion changes to chromate ion
(C) oxidation number of chromium changes from + 6 to + 4
(D) oxidation number of chromium changes from + 4 to +6
उत्तर
dichromate ion changes to chromate ion.
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संबंधित प्रश्न
Calculate the mass percentage of benzene (C6H6) and carbon tetrachloride (CCl4) if 22 g of benzene is dissolved in 122 g of carbon tetrachloride.
Define Molality.
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- express this in percent by mass.
- determine the molality of chloroform in the water sample.
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Define Normality.
Molarity of the solution is ____________.
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w/w (mass percentage)
Define the following modes of expressing the concentration of a solution. Which of these modes are independent of temperature and why?
m (Molality)
Match List-I with List-II:
| List-I | List-II |
| A. ppm | I. molL-¹ |
| B. Molarity | II. No units |
| C. Molality | III. Independent of temperature |
| D. Mole fraction | IV. Very dilute solutions |
Choose the correct answer from the options given below:
Calculated the mole fraction of benzene in a solution containing 30% by mass of its is carbon tetrachloride
Calculate the mass percent of benzene (CoH6) and carbon tetrachloride (ccl4) if 22 g of benzene is dissolved in 122 g of carbon tetrachloride.
138 g ethyl alcohol is mixed with 72 g of water. The ratio of mole fraction of alcohol to water is ______.
250 mL of 0.5 M NaOH was added to 500 mL of 1 M HCl. The number of unreacted HCl molecules in the solution after complete reaction is ______ × 1021. (Nearest integer) (NA = 6.022 × 1023).
A given solution of H2O2 is 30 volumes. Its concentration in terms of molarity is ______.
The mole fraction of a solute in a 100 molal aqueous solution is ______ × 10-2. (Round off to the Nearest Integer).
[Given :Atomic masses : H : 1.0 u, O : 16.0 u]
