The main disadvantage of hard water, is (A) Greater soap consumption (B) Scaling of boilers (C) Corrosion and incrustation of pipes (D) All the above

The main disadvantage of hard water, is 

(A) Greater soap consumption 

(B) Scaling of boilers 

(C) Corrosion and incrustation of pipes 

(D) All the above 

by

1 Answer

Answer :

(D) All the above 

by

Related questions

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Last Answer : (D) All the above 

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Which of the following operational problems relate to the functioning of rapid gravity filter ? 1. Inadequate media comprising filter bed 2. Sludge bulking 3. Mud balls 4. Negative head 5. Incrustation of media (a) 1, 3, 4 and 5 only (b) 1, 2, 3 and 4 only (c) 2, 3, 4 and 5 only (d) 1, 2, 3, 4 and 5

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Use of water having dissolved oxygen in boilers promotes (A) Corrosion (B) Sequestration (C) Scale formation(D) None of these

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Hard water for public water supply is discarded because (A) It consumes more soap (B) It contains lot of turbidity (C) It contains pathogenic bacterias (D) It possesses bad taste and odour

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Which of the following is not property of an alloy? a) strong b)resistant to corrosion c)hard d)Poor conductor of electricity

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The direct shear test suffers from the following disadvantage: (A) Drain condition cannot be controlled (B) Pore water pressure cannot be measured (C) Shear stress on the failure plane is not uniform (D) The area under the shear and vertical loads does not remain constant throughout the test

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(3) Detergents give lather even with hard water Explanation: Soaps are made of materials found in nature. Detergents are synthetic a big drawback of washing with soap is that the minerals in water react with those in soap, leaving an insoluble film. Detergents react less to minerals in water and for all practical purposes are the product of choice for laundry, unless you have very soft water. On the other hand, soap will combine with the magnesium and calcium ions in hard water to create an insoluble residue that can clog drains and stick to clothing.

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(3) Detergents give lather even with hard water Explanation: Soaps are made of materials found in nature. Detergents are synthetic. a big drawback of washing with soap is that the minerals in water react with those in soap, leaving an insoluble film. Detergents react less to minerals in water and for all practical purposes are the product of choice for laundry, unless you have very soft water. On the other hand, soap will combine with the magnesium and calcium ions in hard water to create an insoluble residue that can clog drains and stick to clothing.

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