Biology; Chemistry; Physics: Post your doubts here!

[ayeshaK]

wasted ur energy..

No ! Helping others is nt wasting energy and practice bhi ho gayi

 

[kitecrystal]

4 marks ka kiya answer hoga :\

yeast is added in a container along with some cooled,boiledglucose..container is sealed to ensure that oxygen does not enter,and kept at 20C temperature to maintain anaerobic conditions for fermention.ethanol is prepared as a product of respiration of yeast and is separated by fractional distillation of the mixture.Equation:
C6H12O6 (arrow)2 C2H5OH+H2O

 

[MustafaMotani]

No ! Helping others is nt wasting energy and practice bhi ho gayi

wEll of course helping is not wasting but it was already done.. .However prac hogae..

 

[Dukeofwin]

I am ducked in MCQ's! No problem in Theory!
Any tips people?

 

[ayeshaK]

I am ducked in MCQ's! No problem in Theory!
Any tips people?

Just concentrate and dont first go for correct option directly and luk for reasond dat which option are incorrect and y !! In this way u wuld be sure abt ur answer !!
And have a quick go thru the chapter uz mcqs come frm anywhere

 

[kitecrystal]

The carbonate of metal X is a white solid.
It decomposes when heated to form carbon dioxide and a yellow solid oxide.
What is metal X?
A copper
B iron
C lead
D sodium

 

[kitecrystal]

I am ducked in MCQ's! No problem in Theory!
Any tips people?

do past papers,some mcqs are repeated...

 

[MustafaMotani]

The carbonate of metal X is a white solid.
It decomposes when heated to form carbon dioxide and a yellow solid oxide.
What is metal X?
A copper
B iron
C lead
D sodium

is lead the answer .. ??

 

[ayeshaK]

The carbonate of metal X is a white solid.
It decomposes when heated to form carbon dioxide and a yellow solid oxide.
What is metal X?
A copper
B iron
C lead
D sodium

Lead !

 

[Translucent231]

The carbonate of metal X is a white solid.
It decomposes when heated to form carbon dioxide and a yellow solid oxide.
What is metal X?
A copper
B iron
C lead
D sodium

C lead ,, Lead oxide is yellow

 

[kitecrystal]

is lead the answer .. ??

yeah!how?

 

[Translucent231]

lol simultaneous answering :d

 

[kitecrystal]

Lead !

how?

 

[Aamynims]

The carbonate of metal X is a white solid.
It decomposes when heated to form carbon dioxide and a yellow solid oxide.
What is metal X?
A copper
B iron
C lead
D sodium

I think its lead..
blue is cupper's color, yellow for lead, iron: green/red brown

 

[Dukeofwin]

is lead the answer .. ??

Yup, since Carbonate is white in colour, Metal X is not a tranisitonal metal. Sodium carbonate is very stable to heat and doesn't decompose at all. Lead(II) carbonate decomposes on heating and forms yellow ppt of PbO

 

[bogus]

Important question... merchants guess paper says Dehydration.... what are we supposed to know about it reply please????

 

[MustafaMotani]

yeah!how?

lead produces yellow compunds thats y i guessed...
However sodium cant be broken down by heat, iron and copper dont form yello compounds

 

[kitecrystal]

Yup, since Carbonate is white in colour, Metal X is not a tranisitonal metal. Sodium carbonate is very stable to heat and doesn't decompose at all. Lead(II) carbonate decomposes on heating and forms yellow ppt of PbO

JazakAllah..

 

[kitecrystal]

hey lead is transition metal dont get confuse[/quote
but is in groupIV?????

 

[Aamynims]

Important question... merchants guess paper says Dehydration.... what are we supposed to know about it reply please????

i wanna know tooo!