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Question & Answer Forum

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Satyanarayana answered 4 year(s) , 5 month(s) ago

Difference between luminous and non-luminous flame

Ans: Substances which vaporize during burning gives flame.
The substance which does not vaporize during burning does not produce flame.
Flame is of two types.
1.      Luminous flame...

Asked by Ritambhara

Nov 6

  • 2 Answers
  • 2 Likes
  • 32267 Views
Syeda answered 1 year(s) , 10 month(s) ago

Is water a good or bad conductor of electricity?

water isa goo conductor and pure water is a bad conductor of eLeCTriciTY

Asked by Abcdefgh

Nov 30

  • 17 Answers
  • 2 Likes
  • 22266 Views
Agam answered 1 year(s) , 3 month(s) ago

. Why carbon dioxide gas is used to extinguished fire caused by petrol Diesel or kerosene? Why not water?

In case of oil fires, water is not suitable for extinguishing the fire because diseal is less dense than water and will float in water. As water will spread, such the oil will spread and the fire will become mo...

Asked by Prasheek

Nov 18

  • 5 Answers
  • 3 Likes
  • 16102 Views
Sachin answered 4 year(s) ago

In an experiment 4.5 kg of a fuel was completely burnt.The heat produced was measured to 180000 kJ. Calculate the calorific value of the fuel.

Ans: Calorific value: The amount of heat energy released on complete combustion of 1 kg of a fuel is called calorific value.
It is expressed in a unit called kilo joule per kg (kJ/kg)....

Asked by Arjun

Nov 12

  • 2 Answers
  • 3 Likes
  • 15235 Views
Syeda answered 1 year(s) , 11 month(s) ago

Three examples of non combustible substances.

Answer.


Examples of non-combustible substances are
rock,steel,water,sand etc.       

Asked by Mangesh

Aug 18

  • 6 Answers
  • 4 Likes
  • 15182 Views
Suraj M commented 1 year(s) , 1 month(s) ago

Dry leaves catch fire easily but it is difficult to burn a heap of green leaves ?

Green leaves contain moisture whereas dry leaves do not contain  moisture as a result, the ignition temperature of green leaves is higher than that of dry leaves. Due to this reason, it is difficult to burn

...

Asked by Dhruv

Mar 8

  • 1 Answer
  • 6 Likes
  • 10288 Views
Pranjal answered 4 year(s) , 7 month(s) ago

EXAMPLES OF SLOW COMBUSTION ?

celluler respiration

Asked by Sharanya

Oct 22

  • 5 Answers
  • 0 Like
  • 9735 Views
Swathi answered 3 year(s) , 7 month(s) ago

why are gaseous fuels better than solid and liquid ones?

Calorific value is defined as the amount of heat energy produced on complete combustion of 1 kilogram of a fuel. It is expressed in a unit called kilojoule per kg. The higher the calorific value of a fuel, the...

Asked by Mohit

Aug 23

  • 1 Answer
  • 1 Like
  • 9639 Views
Syeda answered 1 year(s) ago

what is the equation of soda acid fire extinguisher

2NaHCO3 + H2SO4 ⇒ Na2SO4 + 2H2O + 2CO2
                              or
Na2CO3 + H2SO4  ⇒ Na2SO4 + H2O + CO2

Asked by Raj

Mar 4

  • 2 Answers
  • 1 Like
  • 9353 Views
Vaibhav answered 4 year(s) , 3 month(s) ago

WHAT IS CALORIFIC VALUE?

Calorific Value (CV) is a measure of heating power and is dependent upon the composition of the gas. The CV refers to the amount of energy released when a known volume of gas is completely combusted unde...

Asked by Saranya

Dec 19

  • 3 Answers
  • 1 Like
  • 7438 Views
Saloni commented 4 year(s) , 4 month(s) ago

When we blow the air on glowing wood it catches fire.But at the same time, we use a blow of air to extinguish the flame of a candle .why

Hi saloni!
Oxygen is necessary for combustion.
Blowing out a candle makes the candle goes out. Because in candle the flame is due to burning of  vapoutized wax. When we blow the candle the vapou...

Asked by Saloni

Nov 15

  • 1 Answer
  • 3 Likes
  • 6247 Views
Swathi answered 3 year(s) , 7 month(s) ago

Why does Kerosene burn with a blue flame in a wick-stove but produces a yellow flame when burnt in a lamp?

In kerosene lamp yellow flame is produced due to partial combustion of kerosene. Partial combustion is due to lack of oxygen for burning.
But in wick - stove kerosene burns with blue flame. Because in k...

Asked by Sucharita

Aug 14

  • 1 Answer
  • 1 Like
  • 5735 Views
Saloni answered 3 year(s) , 10 month(s) ago

What is flame?

he process of combustion of flammable materials; produces heat, light, and (often) smoke.

Asked by Sara Batool

May 22

  • 3 Answers
  • 2 Likes
  • 5076 Views
Swathi answered 4 year(s) , 3 month(s) ago

Explain experiments showing that oxygen is necessary for combustion

Take a burning candle and cover the burning candle with a glass jar so that the candle is in an air tight room.
After some time the candles dims and goes out. This shows that air (oxygen) is necessary

...

Asked by Saranya

Dec 25

  • 2 Answers
  • 1 Like
  • 5047 Views
Satyanarayana answered 5 year(s) , 1 month(s) ago

What is the difference between burning and combustion

Ans: Combustion:

The oxidation reaction in which high amount of heat is produced called as combustion.

In general fuels like petrol, diesel, Liquefied petroleum gas

...

Asked by Vatsal

Mar 1

  • 1 Answer
  • 0 Like
  • 4352 Views
Shubh answered 4 year(s) , 3 month(s) ago

Types of combustion

Ans: It is the burning of a chemical substance in presence of oxygen. In combustion carbon dioxide along with water vapor releases. Heat also releases during combustion reaction. So combustion is exothermic in...

Asked by Ritambhara

Nov 6

  • 2 Answers
  • 1 Like
  • 3792 Views
Swathi answered 3 year(s) , 7 month(s) ago

Is rusting of iron also be called combustion ?Yes/No?Give reason.

Yes, Rusting is also called as combustion.
Combustion is a chemical process in which substance reacts with oxygen and give off light or heat or both.Similarly rusting is also chemical process which does...

Asked by Aditya

Aug 30

  • 1 Answer
  • 3 Likes
  • 3523 Views
Satyanarayana answered 5 year(s) , 5 month(s) ago

What is slow combustion

Ans: The combustion reactions which take place slowly and give less amount of heat slowly are termed as slow combustion reactions.
 The processes of rusting, digestion of food are few e...

  • 1 Answer
  • 1 Like
  • 3079 Views
Shikhar answered 5 year(s) , 1 month(s) ago

What is the difference between burning and combustion

combustion is defined as process of burning of a substance in the presence of air or oxygen.

burning is a process in light and heat is emitted

Asked by Vatsal

Mar 1

  • 3 Answers
  • 0 Like
  • 2857 Views
Satyanarayana answered 3 year(s) , 7 month(s) ago

why are gaseous fuels better than the solid and liquid ones?

Ans: 
When compared with solid and liquid fuels-
Gaseous fuels posses high calorific values.
No ash production is observed when gaseous fuels burned.

Asked by Mohit

Aug 22

  • 1 Answer
  • 0 Like
  • 2248 Views
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