Answer
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Hint: Water which does not readily produce lather with soap is known as hard water. It is due to the presence of bicarbonates, sulfates, and chlorides of calcium and magnesium in it. These salts get dissolved in it when it passes through the rock or ground. Examples of hard water are seawater, river water, well, and tap water.
Hard water does not produce lather with soap solution readily because $C{a^{2 + }}$ and $M{g^{2 + }}$ ions present in hard water reacts with anions of soap (such as stearate, palmitate, and oleate) to form curdy white precipitates.
For example,
$C{a^{2 + }} + 2{C_{17}}{H_{35}}COONa \to {({C_{17}}{H_{35}}COO)_2}Ca + 2N{a^ + }$
$\text{ (From hard Sodium Stearate Calcium Stearate}$
$\text{ water) (Soap) (curdy white ppt.)}$
As a result, hard water does not form lather with soap until sufficient soap has been added to remove calcium and magnesium ions in the form of white precipitates. Thus, a lot of soap is wasted. Hence, hard water is not good for washing purposes.
Complete step by step answer:
Hard water has an increased boiling point due to which it takes a long time to boil and it also contains salts in it due to which it is not easy to cook pulses in hard water.
The presence of hard water during cooking alters the taste, color, and odor and also reduces the lifespan of the cooked food. Therefore hard water is not preferred for cooking purposes.
So we can conclude that the given statement is false.
So, the correct answer is Option B.
Note: The hardness of water is of two types- Temporary Hardness and Permanent Hardness
Temporary Hardness: - It is because of the presence of bicarbonates of calcium, magnesium, and iron dissolved in water. This type of hardness of water is also known as carbonate hardness. It is named temporary hardness because it can be removed by boiling the water.
Permanent Hardness: - It is because of the presence of chlorides and sulfates of calcium, magnesium, and iron in the water. This type of hardness in water is also known as non-carbonate hardness. It is named permanent hardness because such hardness cannot be removed simply by boiling the water.
Hard water does not produce lather with soap solution readily because $C{a^{2 + }}$ and $M{g^{2 + }}$ ions present in hard water reacts with anions of soap (such as stearate, palmitate, and oleate) to form curdy white precipitates.
For example,
$C{a^{2 + }} + 2{C_{17}}{H_{35}}COONa \to {({C_{17}}{H_{35}}COO)_2}Ca + 2N{a^ + }$
$\text{ (From hard Sodium Stearate Calcium Stearate}$
$\text{ water) (Soap) (curdy white ppt.)}$
As a result, hard water does not form lather with soap until sufficient soap has been added to remove calcium and magnesium ions in the form of white precipitates. Thus, a lot of soap is wasted. Hence, hard water is not good for washing purposes.
Complete step by step answer:
Hard water has an increased boiling point due to which it takes a long time to boil and it also contains salts in it due to which it is not easy to cook pulses in hard water.
The presence of hard water during cooking alters the taste, color, and odor and also reduces the lifespan of the cooked food. Therefore hard water is not preferred for cooking purposes.
So we can conclude that the given statement is false.
So, the correct answer is Option B.
Note: The hardness of water is of two types- Temporary Hardness and Permanent Hardness
Temporary Hardness: - It is because of the presence of bicarbonates of calcium, magnesium, and iron dissolved in water. This type of hardness of water is also known as carbonate hardness. It is named temporary hardness because it can be removed by boiling the water.
Permanent Hardness: - It is because of the presence of chlorides and sulfates of calcium, magnesium, and iron in the water. This type of hardness in water is also known as non-carbonate hardness. It is named permanent hardness because such hardness cannot be removed simply by boiling the water.
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