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Fehling solution and fehling reagent???

Posted by Armaan Gur_Jar 6 years, 1 month ago

3 answers

Fehling A aqueous copper sulphate fehling B alkaline sodium pottasium tartarate it is a distinguish test all aldehyde give this test except benzaldehyde

1Thank You

Yogita Ingle 6 years, 1 month ago

Fehling’s solution is a deep blue alkaline solution which is used to identify the presence of aldehydes or groups that contain any aldehyde functional group -CHO and in addition with Tollen’s reagent to differentiate between reducing and non-reducing sugars.

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Tapan Pandey?? 6 years, 1 month ago

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O and p-nitrophenols are more acidic than phenol? Explain observation??

Posted by Lalit Chaudhary 6 years, 1 month ago

CBSE > Class 12 > Chemistry

1 answers

Tapan Pandey?? 6 years, 1 month ago

Because nitro group is an EWG ..... therefore it decreases the electron density of aromatic ring....

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Acid catalysed dehydration of an alcohol forming an alkene?. Explain mechanism?

Posted by Lalit Chaudhary 6 years, 1 month ago

CBSE > Class 12 > Chemistry

1 answers

Tapan Pandey?? 6 years, 1 month ago

Step I:- protonation of alcohol ..... (Oxygen attract H+) Step II :- removal of water molecule Step III :- deprotonation forms alkene.

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Addition of grignard reagent to the carbonyl group of compound forming an adduct followed by hydrolysis...?? Explain the mechanism of the following reaction??

Posted by Lalit Chaudhary 6 years, 1 month ago

CBSE > Class 12 > Chemistry

1 answers

Tapan Pandey?? 6 years, 1 month ago

Sn1 mechanism....

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Formula for tollen's reagent??????plzz answer .

Posted by Armaan Gur_Jar 6 years, 1 month ago

CBSE > Class 12 > Chemistry

3 answers

Rajat Barwar 6 years, 1 month ago

{Ag(NH3)2}+, The below ans. is also correct. @tapan.

1Thank You

Shatayu Ganvir 6 years, 1 month ago

Ag2O

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Tapan Pandey?? 6 years, 1 month ago

AgNO3 + NH4OH (ammoniacal silver nitrate)

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ANSWER

What is alpha hydrogen in aldol condensation ??? ?? Unable to understand it. ?????

Posted by Armaan Gur_Jar 6 years, 1 month ago

CBSE > Class 12 > Chemistry

2 answers

Tapan Pandey?? 6 years, 1 month ago

0Thank You

Rohit Khandal 6 years, 1 month ago

Alpha hydrogen refers to that hydrogen bonded with alpha Carbon i.e,1 no. Carbon corresponds to carbonyl group in aldol condensation

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ANSWER

What happens when phenol react with sodium dicromate

Posted by Saurabh Dhaundiyal 6 years, 1 month ago

CBSE > Class 12 > Chemistry

3 answers

Vashu Yadav 6 years, 1 month ago

Benzoquinine

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Shatayu Ganvir 6 years, 1 month ago

Bemezene carbocyllic acid

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Tapan Pandey?? 6 years, 1 month ago

Formation of corresponding acid.....I am not sure ?

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Is there any relation between molarity and molality

Posted by Only A User 6 years, 1 month ago

CBSE > Class 12 > Chemistry

3 answers

Tapan Pandey?? 6 years, 1 month ago

M = (M*1000)/{(1000*d)-(M*M2)} .....where, M====molarity ,M2 is molar mass of sloute , and d is density.... . .. And another one..... M1V1= M2V2

1Thank You

Lalit Chaudhary 6 years, 1 month ago

Yes

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Vashu Yadav 6 years, 1 month ago

Hmm d/m= 1/m+mb/1000

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ANSWER

What is formula of molarity if density is given ???

Posted by Only A User 6 years, 1 month ago

CBSE > Class 12 > Chemistry

3 answers

Tapan Pandey?? 6 years, 1 month ago

Change volume by mass /density

1Thank You

Rohit Khandal 6 years, 1 month ago

W/W% * density *10/molar mass of solute

1Thank You

Lakshya Verma 6 years, 1 month ago

%mass × density (gml.) ×10 /molar mass of solute

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ANSWER

What is relation between molarity and normality . Tell me if anyone knows

Posted by Only A User 6 years, 1 month ago

CBSE > Class 12 > Chemistry

3 answers

Yogita Ingle 6 years, 1 month ago

Molarity and Normality are related as follows:

Normality = <nobr>MolarityX Molar mass/Equivalent mass</nobr>

For acids the normality can be calculated with the following formula:

Normality = Molarity x Basicity

To know the value for basicity, count the number of H⁺ ions an acid molecule can give.

For bases the normality can be calculated with the following formula:

Normality = Molarity x Acidity

1Thank You

Tapan Pandey?? 6 years, 1 month ago

1Thank You

Manish Chahal 6 years, 1 month ago

Normality =molarity×n-factor

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ANSWER

Why is co2 better reducing agent than co

Posted by Madhavan Maddy 6 years, 1 month ago

CBSE > Class 12 > Chemistry

1 answers

Manish Chahal 6 years, 1 month ago

Because value of gibbs free energy for Co2 is more negative than that of CO

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ANSWER

Hey guys how are you preparing for chemistry☺️☺️??

Posted by Vashu Yadav 6 years, 1 month ago

CBSE > Class 12 > Chemistry

2 answers

Meghna Sharma 6 years, 1 month ago

By keeping the eyes ?, mind n book ? open..

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Mahesh M 6 years, 1 month ago

Physics modration policy 2020

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Physics moderation of 2020

Posted by Mahesh M 6 years, 1 month ago

CBSE > Class 12 > Chemistry

0 answers

ANSWER

Eqn for synthesis of glyptal

Posted by Promila Tayenjam 6 years, 1 month ago

CBSE > Class 12 > Chemistry

1 answers

Sanchari Roy 6 years, 1 month ago

Glyptal is formed by the combinations of monomers ethylene glycol and pthalic acid.

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ANSWER

Write the mono unit of tyierlene

Posted by Nadhu Panwar 6 years, 1 month ago

CBSE > Class 12 > Chemistry

1 answers

Sanchari Roy 6 years, 1 month ago

Ethylene glycol and terepthalic acid.

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ANSWER

Guys ,mujhe to lagta he iss bar ke mcq polymer,biomolecules, chemistry in everyday life se puchenge,jaisa cbse ne physics me kiya ( e m waves, semi conductors and all) do you all agree with me??

Posted by Tamanna Sharma 6 years, 1 month ago

CBSE > Class 12 > Chemistry

5 answers

Meghna Sharma 6 years, 1 month ago

Kuch bhi aa skta h ab to exam mei

1Thank You

Deepika Rao 6 years, 1 month ago

Shi h jiji

1Thank You

Lakshya ? 6 years, 1 month ago

1Thank You

Rohit Patil 6 years, 1 month ago

Hmmmmmmmmmmmmmum

1Thank You

Advika Thakur 6 years, 1 month ago

Hmm...

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Etard reaction ?

Posted by Reetika Srivastava 6 years, 1 month ago

CBSE > Class 12 > Chemistry

2 answers

Neha Choudhary 6 years, 1 month ago

Toluene react in presence of chromylcholride and converted. Into benzaldehyde

1Thank You

Rohit Patil 6 years, 1 month ago

Chromylchloride reaction is same

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ANSWER

Examples of positive deviation from raoult's law

Posted by Reetika Srivastava 6 years, 1 month ago

CBSE > Class 12 > Chemistry

2 answers

Raj Ritanjit 6 years, 1 month ago

Ethanol dissolved in n-hexane

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Tamanna Sharma 6 years, 1 month ago

Ethanol + acetone,,,,acetone + carbon disulphide

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ANSWER

Abhi tk kuch ni pdha 3 days ke Baad mera exam h . senior Koi strategy bta do please

Posted by Mirza Ubaid 6 years, 1 month ago

CBSE > Class 12 > Chemistry

6 answers

Meghna Sharma 6 years, 1 month ago

Sun dont take tension.......first of all apna syllabus complete kr..kk....coz without completion of syllabus tu confidence gain nhi kr paeyga...aur...chem ke exam mei marks lana is a easy task but fir that ur syllabus must be completed n then go through last 5 yrs papers.....n thats it madam......bahut bdiya score aa jega

1Thank You

Meghna Sharma 6 years, 1 month ago

Listen...........apna admit card mandir mei rakh aa aur har roz uski pooja krle

0Thank You

Rohit Patil 6 years, 1 month ago

Mera bhi exam he??

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Ayush Verma 6 years, 1 month ago

Bhagwaan ka naam lo 108 bar??

3Thank You

Tamanna Sharma 6 years, 1 month ago

Jo hmm pure sal me nahi kar sake abb 3 din me kuch nahi badlega bas jo aata he vahi revise karo,that's all.

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Fairy Lights 6 years, 1 month ago

It's alright!....just take a deep breathe and relax...have some chai and keep your mind cool. Now.....(i will only be talking about physical chem) Chemistry he sooo it neans NCERT ke jo formulae he wo acche se yaad karke apne long term memory me ghusa lo...1. pehle yaad karo. 2.paper lo pen lo and without looking at the book start writing the formulae. 3. Now yaad ho gya ho to a.intext questions karo.b.examples questions karo.c.exercise wale jo questions he na uussme tum book ko dekho and then jo formulae apply ho rhe he usko book me hi likho and then apko jisme nahi ata karna wo copy me practice karo. 4. Yayyyyy hogya. 5. I am sure yeh sab karne ke baad you will become confident. 6. Take atleast 1 and a half day to finish the work and work SMARTLY. 7. PAST PAPERS is a MUST. 8. Abhi kasht kar lo baad me rahat he.

1Thank You

ANSWER

What are emulsion

Posted by Dipanshu Rajput 6 years, 1 month ago

CBSE > Class 12 > Chemistry

1 answers

Fairy Lights 6 years, 1 month ago

Emulsion is a colloidal dispersion. Dispersion phase also liquid and dispersion medium also liquid.

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ANSWER

Biomolecules me figures bnana jaruri h... aur agar haa..t kitne marks me bnana h

Posted by Shalini Singh 6 years, 1 month ago

CBSE > Class 12 > Chemistry

3 answers

Jeevan Mishra 6 years, 1 month ago

Structure of compound draw karna padh sakta hai

0Thank You

Jeevan Mishra 6 years, 1 month ago

Depending on question

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Shiwangee Gupta 6 years, 1 month ago

Draw fig if asked in que

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ANSWER

Why is ka2<<ka1 in water?

Posted by Saptarsi Bandyopadhyay 6 years, 1 month ago

CBSE > Class 12 > Chemistry

1 answers

Fairy Lights 6 years, 1 month ago

It's a dissociation constant. It shows how HCO3- dissociates into H+ and CO3(raised to the power)-2 (carbonate anion)

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If i do only ncert solved question and exemplar question can i get good marks or ibhave to do some more

Posted by Harkaranbir Singh 6 years, 1 month ago

CBSE > Class 12 > Chemistry

3 answers

Harkaranbir Singh 6 years, 1 month ago

Thns

0Thank You

Tamanna Sharma 6 years, 1 month ago

Dude maine physics me kiya but paper ka level vo tha hi nahi, to yeh to chemistry he NCERT enough

1Thank You

Hasan Azam 6 years, 1 month ago

Ncert is enough for board exams of chemistry.dont forget to study intext questions

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ANSWER

What is the chapter wise weightage of chemistry exam ??

Posted by Harkaranbir Singh 6 years, 1 month ago

CBSE > Class 12 > Chemistry

1 answers

Seema Sinha 6 years, 1 month ago

Physcial 23 Organic 28 Inorganic 19

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Kaisi chal rhi sabki tayaari?

Posted by Shreya .. 6 years, 1 month ago

CBSE > Class 12 > Chemistry

1 answers

Nishant Sharma 6 years, 1 month ago

BADIYA CHAL RHI HAI..AAP BTAO?

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Half life of a reaction of nth order.?

Posted by Lakshya Verma 6 years, 1 month ago

CBSE > Class 12 > Chemistry

1 answers

Rajat Barwar 6 years, 1 month ago

Proprtional to (initial concen.)^(1-n).

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Cu2Cl2 and CuCl2 which one is more stable?

Posted by Lakshya Verma 6 years, 1 month ago

CBSE > Class 12 > Chemistry

2 answers

Shatayu Ganvir 6 years, 1 month ago

No, Cu2Cl2 is more stable

0Thank You

Rajat Barwar 6 years, 1 month ago

It should be CuCl2 because in it copper is +2 and hence have more hydration energy due to more charge. Hope this may help u... If u know the correct ans. please tell it.

1Thank You

ANSWER

How to study chemistry in 3 days ? Those who think the same write "yes" ??

Posted by Rishi Vyas 6 years, 1 month ago

CBSE > Class 12 > Chemistry