Tag: hard water and soft water

Questions Related to hard water and soft water

Organic ion exchange resins purify hard water to yield :

chemistry hydrogen and its compounds heavy water study of heavy water hard water and soft water

  1. Distilled water

  2. Only decalcified water

  3. Deionised water

  4. Water having relatively high concentration of $OH^{-}$ion

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Correct Option: B
Explanation:

Organic ion exchange resins are used for water softening. In this process, the $Ca^{+2}$ and $Mg^{+2}$ ions which cause hardness are exchanged for $Na^{+}$ or $K^{+}$ ions due to which the water becomes decalcified or hardness free. Therefore, organic ion exchange resins purify hard water to yield only decalcified water

Hardness of water can be detected with:

chemistry hydrogen and its compounds heavy water study of heavy water hard water and soft water

  1. $Na _{2}CO _{3}$ solution

  2. soap water

  3. dil. $HCl$

  4. acidified $KMnO _{4}$ solution

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Correct Option: B
Explanation:

Hardness of water can be detected with soap water. Water is described as being 'hard' if it does not lather readily with soap. 

'Soft water', on the other hand, is described as the one, which lathers readily with soap. Chemically, natural water is never pure and contains varying amounts of the dissolved impurities absorbed from the natural or man made environment. 
When appreciable concentrations of calcium ions $(Ca^{2+})$ or the magnesium ions $(Mg^{2+})$ in the form of their dissolved salts are contained in water, it becomes hard.

Heavy water $\displaystyle \left( { D } _{ 2 }O \right) $ is used in Atomic Reactors as -

chemistry hydrogen and its compounds heavy water study of heavy water hard water and soft water

  1. Coolant

  2. Controller

  3. Shield

  4. Moderator

Show answer
Correct Option: D
Explanation:

Moderator. e.g. , Heavy water, is a substance used in nuclear reactors of reduce the speed of fast Neutrons produced by nuclear fission.Moderator. e.g. , Heavy water, is a substance used in nuclear reactors of reduce the speed of fast Neutrons produced by nuclear fission.Moderator. e.g. , Heavy water, is a substance used in nuclear reactors of reduce the speed of fast Neutrons produced by nuclear fission.'

Heavy water is used in nuclear reactors as:

chemistry hydrogen and its compounds heavy water study of heavy water hard water and soft water

  1. source of $\alpha-$ particles

  2. slowing down the speed of high energy neutrons

  3. transporting heat of the reactor

  4. heating purpose

Show answer
Correct Option: B
Explanation:

Heavy water is used in nuclear reactors, where it acts as a neutron moderator to slow down neutrons so that they are more likely to react with the fissile $U^{235}$ than with $U^{238}$, which captures neutrons without fissioning.

Heavy water is a compound of :

chemistry hydrogen and its compounds heavy water study of heavy water hard water and soft water

  1. hydrogen and heavier isotope of oxygen.

  2. heavier isotope of hydrogen and heavier isotope of oxygen.

  3. oxygen and heavier isotope of hydrogen.

  4. none of the above

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Correct Option: C
Explanation:

Heavy water is $D _2O$ and it is composed of oxygen and heavier isotope of hydrogen $(D)$.

$ \displaystyle 4{ D } _{ 2 }O+3Fe \xrightarrow[]{red-hot} Fe _{3}O _{4}+gas.$ The gas produced in the above reaction is:

chemistry hydrogen and its compounds heavy water study of heavy water hard water and soft water

  1. $ \displaystyle O _{2}$

  2. $ \displaystyle H _{2}$

  3. $ \displaystyle D _{2}$

  4. none

Show answer
Correct Option: C
Explanation:

Reaction:

$ \displaystyle 4{ D } _{ 2 }O+3Fe \xrightarrow[]{red-hot} Fe _{3}O _{4}+ D _2$. The gas produced in the reaction is deuterium.