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What people are asking?

Ritambhara

Nov 6, 2014

Difference between luminous and non-luminous flame.

This answer has an image. Please click on the question to read more.

Answer (4)

Abcdefgh

Nov 30, 2013

We do not use water during an electric fire as it is a good conductor of electricity.but while doing electrolysis, we add a few drops of H2SO4 to make it a good conductor.So exactly is water a good or bad conductor?

This answer has an image. Please click on the question to read more.

Answer (17)

Mangesh

Aug 18, 2015

Three examples of non combustible substances.

Answer.


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

Answer (6)

Prasheek Shashikant

Nov 18, 2013

     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...

Answer (5)

Arjun R.Unnithan

Nov 12, 2013

I found the answer as 40000 KJ/Kg but the answer in the Learn Next NCERT Science Solution it is given as 4000KJ/Kg.When I referes to the Calculator it shown that 180000/4.5= 40000.

solution=  180000/4.5 
=  1800000/4.5 as the decimal goes to N = numerator 
=4000kj/kg
ok

Answer (2)

Dhruv Tanwar

Mar 8, 2015

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

 Green leaves do not catch fire easily. For  any substance to burn it has to reach its ignition temperature. The Ignition temperature is the lowest temperature at which a material catches fire.
...

Answer (2)

Mohit Dubey

Aug 23, 2015

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. When a gaseous fuel burns it gives off a great deal of energy .

 

And unl...

Answer (2)

Sharanya

Oct 22, 2013

EXAMPLE OF SLOW COMBUSTION ?

celluler respiration

Answer (5)

Raj Sharma

Mar 4, 2014

what is the equation of soda acid fire extinguisher?


Answer.
2NaHCO3 + H2SO4 ⇒ Na2SO4 + 2H2O + 2CO2

Answer (2)

S Saran Nath

Dec 19, 2014

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 comple...

Answer (3)

Ritambhara

Nov 6, 2014

Difference between luminous and non-luminous flame.

This answer has an image. Please click on the question to read more.

Answer (4)

Abcdefgh

Nov 30, 2013

We do not use water during an electric fire as it is a good conductor of electricity.but while doing electrolysis, we add a few drops of H2SO4 to make it a good conductor.So exactly is water a good or bad conductor?

This answer has an image. Please click on the question to read more.

Answer (17)

Mangesh

Aug 18, 2015

Three examples of non combustible substances.

Answer.


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

Answer (6)

Prasheek Shashikant

Nov 18, 2013

     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...

Answer (5)

Arjun R.Unnithan

Nov 12, 2013

I found the answer as 40000 KJ/Kg but the answer in the Learn Next NCERT Science Solution it is given as 4000KJ/Kg.When I referes to the Calculator it shown that 180000/4.5= 40000.

solution=  180000/4.5 
=  1800000/4.5 as the decimal goes to N = numerator 
=4000kj/kg
ok

Answer (2)

Dhruv Tanwar

Mar 8, 2015

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

 Green leaves do not catch fire easily. For  any substance to burn it has to reach its ignition temperature. The Ignition temperature is the lowest temperature at which a material catches fire.
...

Answer (2)

Mohit Dubey

Aug 23, 2015

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. When a gaseous fuel burns it gives off a great deal of energy .

 

And unl...

Answer (2)

Sharanya

Oct 22, 2013

EXAMPLE OF SLOW COMBUSTION ?

celluler respiration

Answer (5)

Raj Sharma

Mar 4, 2014

what is the equation of soda acid fire extinguisher?


Answer.
2NaHCO3 + H2SO4 ⇒ Na2SO4 + 2H2O + 2CO2

Answer (2)

S Saran Nath

Dec 19, 2014

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 comple...

Answer (3)

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