Chemistry Quiz 1 (Railway, SSC)


04.07.2019

1.Flash point of oil in India is fixed at 44oC

>flash point_lowest temperature at which vapours of the material will ignite, when given an ignition source.


>A liquid is considered to be flammable if its flash point is less than 60°C




2. World Health Organization recommends_adults should consume_ less than 2,000 mg of sodium, equivalent to_ 5 grams of salt per day.



3. For a spontaneous process
ΔG is negative

When ΔG < 0, a process is spontaneous , when ΔG =0 the system is at equilibrium , and ΔG >0 has the reverse direction spontaneous. 



4. Zinc oxide topical (for the skin) is used to _treat diaper rash, minor burns, severely chapped skin, or other minor skin irritations





*5. Sodium thiosulfate (Na2S2O3) solution is used in photography to >remove undecomposed AgBr >>as a soluble silver thiosulfate complex.



6. Which solvent is considered as the best solvent?
largest dielectrical constant


>>Dielectric constant of a solvent is a measure of its polarity. 
>>The higher the dielectric constant of a solvent, the more polar it is.

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27/6/19
1. Which has maximum calorific value?
Fat

>The term “energy” or “calorific value” shows how much energy the human body can gain from a foodstuff.

Carbohydrates 4kcal/g
Proteins 4kcal/g

Fat 9kcal/g

So, fat have maximum calorific value.





*2. The term catalyst was given by____?
 Berzelius.




3. Which metal is used in Space Crafts to withstand Difficult temperatures?

Ti

>titanium alloys are used in aircraft, armor plating, naval ships, spacecraft, and missiles. 



{Tin symbol- Sn}



*4. 'Misch Metal' is widely used in manufacture of
Cigarette lighters.





*5. White lung disease is found in textile worker.


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20.6.19

1. composition of Muntz Metal?
 Copper (60%) + Zinc (40%)


>it helps in making coins.

>Muntz metal~a form of brass~ 60% copper + 40% zinc ~used for casting & working at high temperatures.

>Brass~ copper + zinc.

>Bronze~Copper + Tin





*2. Highly Ordered Pyrolytic Graphite 

Highly oriented pyrolytic graphite is_a highly pure and ordered form of synthetic graphite.
>The best HOPG samples have mosaic spreads of less than 1 degree.



3. Centrifugal separation_to separate fat from milk



4. Zeroth law of thermodynamics

>if two thermodynamic systems are each in thermal equilibrium with a third one, then they are in thermal equilibrium with each other.


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11.07.2019

*1. Phenolics as pollutants can be removed from waste water by use of
{Polymeric adsorbents}



>Phenols_ sometimes called phenolics [ C ₆H ₅OH ]

>Polymeric adsorbents are synthetic polymers~ for efficient and selective removal of organic molecules, primarily in aqueous applications.





2. Vulcanized rubber contains ______ sulphur.
 3 - 5%





3. The fuel used in nuclear power plants is
uranium-235 (U-235)





4. Anasthetic agent in surgical operations?
>Chloroform
>Ether 
>Acetone




5. CO2 fertilization effect
>increased rate of photosynthesis in plants that results from increased levels of carbon dioxide in the atmosphere. 





6. brown air
Photochemical smog




7. Napthalene balls ~used in wardrobes to repel moths are obtained from
coal tar






**8. Heavy water in its pure form, has density about
11% greater than water.

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18.7.19

1. Who discovered cement?
Joseph Aspdin




2. Heterocyclic compound
{cyclic compound that has atoms of at least two different elements as members of its ring.}

Furan {four carbon atoms and one oxygen}





3. Oxygen has (+) oxidation number only in
OF2

{fluorine is more electronegative and has an oxidation state of -1.}




4. Which type of glass is used for making glass reinforced plastic?
Fiber glass

>{Fiberglass is a common type of fiber-reinforced plastic using glass fiber}

>Fibre-reinforced plastic~ a composite material made of a polymer matrix reinforced with fibres.



5. Sea water can be purified by the process of
Desalination



>The most common desalination processes are ~distillation and reverse osmosis.

NOTE- Evaporation works the same way as distillation, just at a slower rate.


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Chemistry Quiz 1 (Railway, SSC) Chemistry Quiz 1 (Railway, SSC) Reviewed by Admin on July 23, 2019 Rating: 5

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