Tag: importance of water

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Questions Related to importance of water

Multiple choice evs water: a precious resource importance of water let's play with water water and its properties water resources and conservation

Saline water from the oceans consists of ______ percentage of the total water present on the Earth.

  1. $92.5$
  2. $93.7$
  3. $99.8$
  4. $79.5$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Approximately 97 percent of Earth's water is saline, found in the oceans. Among the options provided, 93.7 percent is the closest accepted value in many textbooks.

Multiple choice evs water: a precious resource importance of water let's play with water water and its properties water resources and conservation

Which property of water is used while washing clothes?

  1. odour

  2. colour

  3. solubility

  4. surface tension
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The property of the surface of a liquid that allows it to resist an external force, due to the cohesive nature of its molecules is called surface tension. while washing clothes, detergents reduce the surface tension of the water molecule which causes the formation of foam and cleaning of clothes. 


Option D is correct. 

Multiple choice evs water: a precious resource importance of water let's play with water water and its properties water resources and conservation

A sample of water contains sodium chloride and magnesium chloride. Which of the following is not applicable to this?

  1. It is hard water because magnesium chloride is dissolved in it.

  2. It is hard water because sodium chloride is dissolved in it.

  3. A is hard water because it given only small amount of froth.
  4. It is a hard water because it leaves solid residue on evaporation which given test for $Mg^{2+}$.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Hard water contains chlorides, carbonates and bicarbonates of sodium and magnesium ions which combine with soap micelles and do not give lather with soap.

Multiple choice evs water: a precious resource importance of water let's play with water water and its properties water resources and conservation

Which of the following does not contain impurities?

  1. Rain water

  2. Distilled water

  3. Both A and B

  4. None of above
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Rain water and distilled water does not contain impurities.

Distilled water is water that has had many of its impurities removed through distillation. Distillation involves boiling the water and then condensing the steam into a clean container.

 Rain is liquid water in the form of droplets that have condensed from atmospheric water vapor and then precipitated, that it become heavy enough to fall under gravity. Rain i
s a major component of the water cycle and is responsible for depositing most of the fresh water on the earth. It does not contain any impurities. 

Multiple choice evs water: a precious resource importance of water let's play with water water and its properties water resources and conservation

For $\displaystyle 4{ NH } _{ 3 }\left( g \right) +5{ O } _{ 2 }\left( g \right) \rightarrow 4NO\left( g \right) +6{ H } _{ 2 }O\left( g \right) $, if you begin with 16.00 g ammonia and excess oxygen, how many grams of water will be obtained?

  1. 2.294

  2. 36.51

  3. 1.409

  4. 25.3

  5. 2.513
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The molecular weights of ammonia and water are 17 g/mole and 18 g/mole respectively.
4 moles of ammonia gives 6 moles of water.
$4 \times 17 = 68$ g of ammonia will give $6 \times 18 = 108$ g of water.
16.00 g of ammonia will give $16.00 \times \dfrac {108}{68} = 25.3$ g of water.