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Why does the white precipitate of silver halide became coloured in the presence of dye eosin

Posted by Bharti Jha 6 years, 11 months ago

1 answers

Yogita Ingle 6 years, 11 months ago

White coloured precipitate of silver halide becomes coloured in the presence of dye eosin because dye eosin (coloured) gets adsorbed on the surface of silver halide precipitate. White precipitate of silver chloride becomes coloured due to adsorption of pigments of eosin dye.

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ANSWER

I am find chemistry last year paper

Posted by Abhimanyu Singh 6 years, 11 months ago

CBSE > Class 12 > Chemistry

1 answers

Yo Yo Honey Singh ? 6 years, 11 months ago

Go to the CBSE official website that is cbse.nic.in you will read the previous year question paper

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If the density of water of a lake is 1.25g/mL and 1kg of lake water contains 92g of Na+ ions, calculate the molarity of Na+ ions in this lake water. (HOTS)

Posted by Ash Thunderbird ✔ 6 years, 11 months ago

CBSE > Class 12 > Chemistry

3 answers

Harisha Goothy 6 years, 11 months ago

Yoooo...high buddy ash thunderbird ..xD

0Thank You

Ash Thunderbird ✔ 6 years, 11 months ago

I don't remember honestly what I was say, maybe I was high ? But I'm sure I said you to practice name reactions. Put all of the papers you practiced on the wall so you can see them!

1Thank You

Harisha Goothy 6 years, 11 months ago

Ash thunderbird ..i didn't get what you were saying yesterday to my organic chemistry question

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The rate of a first order reaction is 004 mol/litre sec at 10 seconds and 0.03 mol/ litre sec at 20 seconds after initiation of reaction . The half life period of reaction is

Posted by Sonu Kumar 6 years, 11 months ago

CBSE > Class 12 > Chemistry

0 answers

ANSWER

Write and draw monomer of Buna-N polymer

Posted by Himanshu Sharma 6 years, 11 months ago

CBSE > Class 12 > Chemistry

3 answers

Priyanka Kumari 6 years, 11 months ago

Buta 1,3 diene and acrylonitrile

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Shaista Parveen 6 years, 11 months ago

It is prepared by copolymerization of 75% buter 1,3diene and 25% acrylonitrile. nCH2=CH-CH=CH2+nCH2=CH(CN)<~~~~~~~~(gives rise to) -[CH2-CH=CH-CH2CH2-CH(CN)-] Buna N

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Sanu Singh 6 years, 11 months ago

I don't think it is possible at this platform. You can reffer to ncert

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Under what condition a quartz can be converted into glass ?

Posted by Priya Singh 6 years, 11 months ago

CBSE > Class 12 > Chemistry

3 answers

Sanu Singh 6 years, 11 months ago

Heating quartz under high pressure and temperature then cooling it emmediatly forms quartz glass

1Thank You

Ash Thunderbird ✔ 6 years, 11 months ago

Heat quartz followed by immediate cooling, and you get glass. Boom!

1Thank You

Gulshan Saini 6 years, 11 months ago

by cooling it rapidly

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ANSWER

What is absolute alcohol?

Posted by Aryan Singh 6 years, 11 months ago

CBSE > Class 12 > Chemistry

1 answers

Yogita Ingle 6 years, 11 months ago

Absolute alcohol is 100% ethanol which is prepared from rectified spirit.
Absolute alcohol is prepared by Azeotropic distillation method. Rectified spirit is mixed with a suitable amount of benzene and subjected to fractional distillation. The last fraction at 351 K b.p is absolute alcohol.

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Sir i am not able to understand the difference between enzyme as drug targets and receptor as drug target

Posted by Anshuman Akela 6 years, 11 months ago

CBSE > Class 12 > Chemistry

1 answers

Yogita Ingle 6 years, 11 months ago

Enzymes as Drug Targets: The catalytic function of an enzyme can be explained with the help of its properties. Enzymes have active sites which provide a binding site for the substrates where it is attacked by the reagent. Additionally, enzymes offer functional groups that will attack the substrate necessary for the chemical reactions.A drug-enzyme interaction will interrupt this catalytic action and such drugs are called enzyme inhibitors. An enzyme inhibitor drug can accomplish this by interfering with the active site of the enzyme. There are two types of inhibitor drugs- competitive inhibitors and non-competitive inhibitors.

Receptors as Drug Targets: Receptors are proteinaceous compounds which help in the cell-to-cell communication in the body. These are present on the cell membranes which act as a mediator between inside and outside world of the cell. They receive the messages (chemical messages) from the neurons through messengers. The binding of this messenger will alter the shape of the receptors which help to transfer message inside the cell. Receptors are specific i.e., every chemical messenger will not be accommodated on every receptor. Drug-receptor interaction also follows the same working principle. Drugs will block the binding site and thus block the messages to the cell. A drug that inhibits the receptor activity is called antagonist.

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Value of ph in terms of log and H+

Posted by Sachin Singh 6 years, 11 months ago

CBSE > Class 12 > Chemistry

1 answers

G H 6 years, 11 months ago

pH=log[H^+]

3Thank You

ANSWER

How i top in English class 12

Posted by Harshit Pratap Singh 6 years, 11 months ago

CBSE > Class 12 > Chemistry

2 answers

Abhinav Sharma 6 years, 11 months ago

I don't think u can top!

0Thank You

Deepak Jindal 6 years, 11 months ago

By studing and hard working

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Anion of first transition series metal in which the oxidation state of metal is equal to its group number

Posted by Neha Bisht 6 years, 11 months ago

CBSE > Class 12 > Chemistry

1 answers

Sanvi Sharma 6 years, 11 months ago

Transition series elements r all metals , why do they form anion ?i didn't get u properly !

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ANSWER

How will you convert formaldehyde to benzylalcohol

Posted by Manpreet Kaur 6 years, 11 months ago

CBSE > Class 12 > Chemistry

1 answers

Ash Thunderbird ✔ 6 years, 11 months ago

React Formadehyde with C6H5MgBr (grignard reagent) to form C6H5CH2OMgBr which after hydrolysis forms benzyl alcohol :)

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ANSWER

Someone plz lemme know how to do these frigging organics!!!!

Posted by Harisha Goothy 6 years, 11 months ago

CBSE > Class 12 > Chemistry

3 answers

Harisha Goothy 6 years, 11 months ago

Ash thunderbird...what did you say....i don't get u bruh

1Thank You

Ash Thunderbird ✔ 6 years, 11 months ago

First of all, language! Second ??? (dude's right) Third, consider buying a small whiteboard to practice ?

2Thank You

Bharat Singh Rathore 6 years, 11 months ago

First write all naming rxns in one paper ..and than hard nd important rxns...and than write all the ptoperties....

2Thank You

ANSWER

Someone plz tell how do u exactly learn chemistry organics... should we learn the whole chapter or only the behind questions...or wat!!!!

Posted by Harisha Goothy 6 years, 11 months ago

CBSE > Class 12 > Chemistry

5 answers

Sanvi Sharma 6 years, 11 months ago

Definitely ?

0Thank You

Harisha Goothy 6 years, 11 months ago

Thankz ...yooo bruh ..sanvi sharm..ill soon venture out on organic chemistry..and i too hope i remember the rxtnz

0Thank You

Sanvi Sharma 6 years, 11 months ago

Yup ,first read out whole chapter then question urself as if someone is asking u dont try to buttify everything rather think properly like if u r jst doing preparation of say basic alkane then u r finishing many chapters properties .so try to correlate the thing nd read. Hope it'll work for u ?

1Thank You

Harisha Goothy 6 years, 11 months ago

Yoooo..but organic chemistry is said to b volatile...?... how are you doing the chapter..are you learning all the naming reactions and preparation methods...??

0Thank You

Sanvi Sharma 6 years, 11 months ago

First thing u should have interest . Its easy buddy ! Just read NCERT text book u will get the concept clearly .

3Thank You

ANSWER

Conversion of nitrobenzen to ethane

Posted by Ajay Arya 6 years, 11 months ago

CBSE > Class 12 > Chemistry

1 answers

Sanvi Sharma 6 years, 11 months ago

It's quite longer process but we can. 1.NaNO2+HCL=aniline 2.Sn/HCL=benzene diazonium chloride Then 3.heating with H3PO2=benzene you'll get . After that 4.Ozonolysis of benzene will give u glyoxal 5.redn of glyoxal by Red P &HI . ?

1Thank You

ANSWER

Define physical chemistry

Posted by Mahi Singh 6 years, 11 months ago

CBSE > Class 12 > Chemistry

0 answers

ANSWER

How many types of crystal

Posted by Anshu Priya 6 years, 11 months ago

CBSE > Class 12 > Chemistry

1 answers

Surbhi . 6 years, 11 months ago

There are four types of crystals: covalent ,ionic ,molecular, and metallic

2Thank You

ANSWER

Na formula

Posted by Ani Tayem 5 years, 8 months ago

CBSE > Class 12 > Chemistry

2 answers

Abhinav Sharma 6 years, 11 months ago

No formula

0Thank You

Prangana Phukon 7 years ago

Sodium ...but what formula?

2Thank You

ANSWER

why no2 is dimerise

Posted by Sachin Pandey 7 years ago

CBSE > Class 12 > Chemistry

1 answers

Sanu Singh 7 years ago

Nitrogen have 5 electrons in its valence shell from which one pair of electron is shared with oxygen, the other pair is stable as they are of opposite spin but one unpaired electron makes the molecule a little unstable. So, two such unstable no2 molecules dimerise by the bonding of their unpaired elecrons that made them unstable and finally, no unpaired electron is left and the dimerised structure becomes stable.

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ANSWER

The radius of anion of an ionic solid is 100pm. Find the radius of cation which just fits in its (1)cubic (2)octahedral (3)tetrahedral

Posted by Sahdev Shekhawat 7 years ago

CBSE > Class 12 > Chemistry

0 answers

ANSWER

Why meta nitro aniline is formed in the nitration of aniline?

Posted by Ankit Pathak 7 years ago

CBSE > Class 12 > Chemistry

1 answers

Sanvi Sharma 6 years, 11 months ago

Ortho or para nitro aniline will form .coz NH2 is strongly activating and ortho para directing group.

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What is +I and -I effect?

Posted by Vandna Yadav 7 years ago

CBSE > Class 12 > Chemistry

1 answers

Prangana Phukon 7 years ago

+I is shown by electron donating group and -I effect by electron attracting group !! Also there are many more factors affected by it lile alkyl groups ,for example = on increasing the degree 1°<2°<3° +I increases...for -I effect on electronegativity increase -I increases

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ANSWER

I'm unable to understand organic chemistry. What should I do?

Posted by Harshit Mishra 7 years ago

CBSE > Class 12 > Chemistry

5 answers

Honey ☺☺☺ 7 years ago

Read the concept hundred times definitely you will get the goal. Best of luck

0Thank You

Sanu Singh 7 years ago

Write almost 10 reactions a day and learn them. In first attempt take the help of book, second time take help of the book ut just by looking at it twice or thrice then third time do it yourself. Follow the same for further upcomming days. everyday, new 10 reactions and then on sunday do again all those reactions that you did in that whole weak. Then those reactions will just flow like water in your mind. Remember it is hard... Because if it won't be hard, it won't be hars work???

0Thank You

Prangana Phukon 7 years ago

While you read ..read it loudly as if you are teaching someone !! And write it as if you are explaining to someone!! I think it will really help you .

3Thank You

Harshit Mishra 7 years ago

But I usually forget it all, as soon as I learn it.

1Thank You

Prangana Phukon 7 years ago

Take help from your teacher!!

2Thank You

ANSWER

Ncert book is enough for study?

Posted by Jaismeen Kaur Brar 7 years ago

CBSE > Class 12 > Chemistry

1 answers

Prangana Phukon 7 years ago

Yes for boards ofcource

2Thank You

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Why soaps does not form in hard water?

Posted by Kinshuk Saini 7 years ago

CBSE > Class 12 > Chemistry

2 answers

Kinshuk Saini 6 years, 11 months ago

Thank u

1Thank You

Yogita Ingle 7 years ago

Soaps are sodium or potassium salts of long-chain fatty acids. Hard water contains calcium and magnesium ions. When soaps are dissolved in hard water, these ions displace sodium or potassium from their salts and form insoluble calcium or magnesium salts of fatty acids. These insoluble salts separate as scum.

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ANSWER

Which is the best u tube channel for chem

Posted by Nav Ghuman 7 years ago

CBSE > Class 12 > Chemistry