A sample of well water contains 140 gm/m3 Ca2+ ions and 345 gm/m3 Na+ ions. The hardness of the sample of water, expressed in terms of equivalent CaCO3 in gm/m3 is (assuming atomic masses of Ca :40, Na : 23, C : 12, O : 16) ?

Related Mcqs:

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   A. 1/9 B. 8/9 C. 1/2 D. 5/9...

2. A vessel of volume 1000 m3 contains air which is saturated with water vapour. The total pressure and temperature are 100 kPa and 20°C respectively. Assuming that the vapour pressure of water at 20°C is 2.34 kPa, the amount of water vapour (in kg) in the vessel is approximately ?

   A. 17 B. 20 C. 25 D. 34...

3. N2 content in a urea sample was found to be only 42%. What is the actual urea content of the sample? (Molecular weight of urea = 60) ?

   A. 80% B. 90% C. 95% D. 98%...

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   A. AB3 B. A2B3 C. A2B D. AB2...

5. In _______________ process, ions of salts react with water to produce acidity or alkalinity ?

   A. Hydration B. Hydrolysis C. Electrolysis D. Dialysis...

6. Concentration of a solution expressed in terms of _______________ is independent of temperature?

   A. Molarity B. Normality C. Molality D. None of these...

7. Atoms of the same element, but of different masses are called__________________?

   A. Isobars B. Isotones C. Isotopes D. None of these...

8. pH value of a solution containing equal concentration of hydroxyl and hydrogen ions will be_________________?

   A. 0 B. 10 C. 7 D. 14...

9. In the reaction, Ca + 2H2O = Ca(OH)2 + H2; what volume (c.c.) of hydrogen at STP would be liberated, when 8 gm of calcium reacts with excess water ? (Atomic weight of calcium = 40) ?

   A. 4480 B. 2240 C. 1120 D. 0.4...

10. The vapor pressures of benzene and toluene are 3 and 4/3 atmospheres respectively. A liquid feed of 0.4 moles of benzene and 0.6 moles of toluene is vaporised. Assuming that the products are in equilibrium, the vapor phase mole fraction of benzene is_________________?

    A. 0.4 B. 0.6 C. 0.8 D. 0.2...