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What is the effect of increasing pH on K...

What is the effect of increasing pH on `K_2Cr_2O_7` solution?

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In aqueous solution, we have `Cr_(2)O_(7)^(2-)+H_(2)O to 2CrO_(4)^(2-)+2H^(+)`. When `pHlt` (acidic medium),it exists as `Cr_(2)O_(7)^(2-)` and colour is orange. When `pHgt7` (basic medium ),it exits as `CrO_(4)^(2-)` and colour is yellow.
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5.1 g sample of H_2O_2 solution containg x%H_2O_2 by weight requires x " mL of " K_2Cr_2O_7 solution for complete oxidation under acidic condition. What is the molarity of K_2Cr_2O_7 solution?

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RESONANCE ENGLISH-D BLOCK ELEMENTS-EXERCISE-3 PART-III
  1. Why among the lanthanides Ce,(III), can be easily oxidised to Ce(IV) (...

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  2. Explain why E^(@) for Mn^(3+)//Mn^(2+) couple is more positive than th...

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  3. What is the effect of increasing pH on K2Cr2O7 solution?

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  4. What is the basic difference between the electronic configurations of ...

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  5. Why do transition elements shows variable oxidation states?

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  6. Give reasons for each of the following: (i) Size of trivalent lantha...

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  7. The E^(@) value in respect of the electrodes chromium (Z=24), manganes...

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  8. The outer electronic configuration of two members of the lanthanoid se...

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  9. Assign reason for each of the following statement: (i) The largest n...

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  10. Write all possible oxidation states of an element having atomic number...

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  11. Why is +2 oxidation state of manganese quite stable while the same is ...

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  12. How is the variability in oxidation states of transition metals differ...

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  13. Write the electronic configuration of the element with atomic number 1...

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  14. (a) Describe the general trends in the following properties of the fir...

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  15. How would you account for the fact that the transition metals and thei...

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  16. Assign reasons for the following : (i) The enthalpies of atomisatio...

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  17. How would you account for the fact that actinoids exhibit a larger num...

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  18. The weak acid, HA has a Ka of 1×10^(−9) . If 0.1 mol of this acid is ...

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  19. Explain the following observations: (i) Generally there is an increa...

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  20. How would you account for the following? (i)The atomic radii of the...

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