chemistry help needed

[Vogue]

questions that say about diffusion of gases, and their collection, how is it determined if a gas is heavier or lighter than AIR? in this, wat is the mass of air taken to compare that particular gas from air?

 

[multixamza01]

questions that say about diffusion of gases, and their collection, how is it determined if a gas is heavier or lighter than AIR? in this, wat is the mass of air taken to compare that particular gas from air?

I'll refer to air as gas , even though it's not , just for the sake of understanding.
Answer:

Well take any mass of air and an equal mass of the sample gas. mix the two gases in a closed container .If air rises and the sample gas sinks , then the sample gas is heavier then air. But if air sinks and the sample rises then the sample is lighter then air.

No there will be no reaction between the two , as air is a mixture of gases.

 

[Vogue]

the particular question about which i asked was from chemistry ATP. It just said that how NH3 gas will b collected? With that were a few set up instruments of upward and downward displacement. the answer to that question was that NH3 is obtained by upward displacement. now upward displacement is only carried out if the gas is lighter than air. my question is that how would i know if NH3 is lighter or heavier than air?

 

[InshallahAajaega]

well !!! in my opinion u dont need that type of knowledge ryt now !!! air is 79% N2 and 20 % O2 !!! whereas NH3 is 25% N and 75% H !!! so its obvious that air is heavier due to its comonents being heavier and denser molecules !!!

 

[Vogue]

well !!! in my opinion u dont need that type of knowledge ryt now !!! air is 79% N2 and 20 % O2 !!! whereas NH3 is 25% N and 75% H !!! so its obvious that air is heavier due to its comonents being heavier and denser molecules !!!

will u please tell me that how is NH3 25% and H 75%......?

 

[InshallahAajaega]

sorry for late reply !!! NH3 is 75% hydrogen coz it has 3 out of four molecules of hydrogen and 1 out of four molecules of nitrogen !!!
the Mr's dont compare and tht makes it lighter !!!

 

[Vogue]

sorry for late reply !!! NH3 is 75% hydrogen coz it has 3 out of four molecules of hydrogen and 1 out of four molecules of nitrogen !!!
the Mr's dont compare and tht makes it lighter !!!

ooo i c.....thank u

 

[InshallahAajaega]

gud luck fr the ppr !!!

 

[A star]

just for information any gas with mr less than 30 will be lighter than air as it is the general considred Mr of air