Biology; Chemistry; Physics: Post your doubts here!

[kirann]

there's an easy way to know what thing is ester...
look for CO2C......or....... COOC (same thing)
and if you find it..... its an ester

thanks

 

[kirann]

i think it should be D but its B how?

 

[kirann]

NITROGEN kahan se agya????
C is the answer

 

[DaniyalK]

i think it should be D but its B how?
View attachment 43311

HCL will react with Na2CO3 and not with NaCl. NaOH won't react with either of them.

 

[DaniyalK]

NITROGEN kahan se agya????
C is the answer

lol this took me by surprise too until someone explained air contains 79% N2 so it will be in the test tube.

 

[kirann]

lol this took me by surprise too until someone explained air contains 79% N2 so it will be in the test tube.

lol ok

 

[afrolina]

Did anyone give english paper 2 exam???????????????????????????????

 

[kirann]

Did anyone give english paper 2 exam???????????????????????????????

yeah i did

 

[DaniyalK]

Everyone did.

 

[kirann]

answer is B

 

[The Frozen_nightmare]

Can anyone give a summary for the conditions for the organic chemistry reactions ?

 

[Ram97]

answer is B View attachment 43317

Copper Carbonate decomposes on heating to Copper Oxide and CarbondiOxide.
Copper Oxide is black in colour

 

[kirann]

does ONLY alkanes undergo combustion reaction ??

 

[Ram97]

Can anyone give a summary for the conditions for the organic chemistry reactions ?

Dehydration of Ethanol makes Ethene: Conc.H2SO4 (dehydrating agent) and temp. 180
Hydrogenation (Alkenes) for making margarine: Nickel (catalyst) and temp. 180
Making alcohol from alkene: H3PO4 (Catalyst) temp. 300 atp. 70-90
Fermentation of Sugar to make Alcohol: Yeast (Zymase) at rtp
Oxidation of alcohol to carboxylic acid: air, acidifies KMnO4, and bacteria (Mycoderma Aceti)

Hope it helps

 

[Ram97]

does ONLY alkanes undergo combustion reaction ??

No, alkenes and carboxylic acids also

 

[kirann]

No, alkenes and carboxylic acids also

no alcohols?

 

[Ram97]

no alcohols?

Also in alcohols Not in carboxylic

 

[The Frozen_nightmare]

Dehydration of Ethanol makes Ethene: Conc.H2SO4 (dehydrating agent) and temp. 180
Hydrogenation (Alkenes) for making margarine: Nickel (catalyst) and temp. 180
Making alcohol from alkene: H3PO4 (Catalyst) temp. 300 atp. 70-90
Fermentation of Sugar to make Alcohol: Yeast (Zymase) at rtp
Oxidation of alcohol to carboxylic acid: air, acidifies KMnO4, and bacteria (Mycoderma Aceti)

Hope it helps

Thank you so much , Btw for the Dehydration of ethanol, should you heat it under reflux ?

 

[Ram97]

Thank you so much , Btw for the Dehydration of ethanol, should you heat it under reflux ?

No it is used in oxidation of ethanol

 

[kirann]

ANSWER IS A