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What is rigidity

Posted by Nandan Tiwary 7 years, 2 months ago

CBSE > Class 12 > Chemistry

1 answers

G K 7 years, 2 months ago

inability to be to bent or be forced out of shape.

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ANSWER

If 60g of H is dissolved with 30g of chlorine to often a solution of 2 liter of HCL. During the formation of HCL specific conductance of where 3.6 multiple 10 power -4Scm-2. A) calculated it equivalent conductance B) determine the molar conductance?

Posted by Ligang Sungka 7 years, 2 months ago

CBSE > Class 12 > Chemistry

1 answers

We Ayush 7 years, 2 months ago

Is answer 8.52

1Thank You

ANSWER

What is residual attractive force

Posted by Krishna Sah 7 years, 2 months ago

CBSE > Class 12 > Chemistry

1 answers

Aisha Gupta 7 years, 2 months ago

The atom in the bulk is surrounded in all direction and hence the forces of attraction are balanced .....but the forces of attraction acting outside are not balanced this forces are called residual attractive forces and the forces provides a unique properties to the surface.

1Thank You

ANSWER

Explain the preparation of amines from azides

Posted by Tanmay Rastogi 7 years, 2 months ago

CBSE > Class 12 > Chemistry

6 answers

G K 7 years, 2 months ago

Yeah...its Staudinger Rxn...ur thinking is correct...?

1Thank You

We Ayush 7 years, 2 months ago

Me ayush parija

1Thank You

We Ayush 7 years, 2 months ago

Any other method is there .pls tell me i will add to my knowledge

0Thank You

We Ayush 7 years, 2 months ago

It is staudinger rreaction i think

0Thank You

Ayush Parija 7 years, 2 months ago

Amines can be prepared from azides by staudinger reaction.R N3 on reaction with pph3 to give iminophosphorane on hydroyslus give primary amine .if you want mechanism i can give the mechanism

2Thank You

G K 7 years, 2 months ago

Reduction of azides gives ammines ......

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ANSWER

Give mechanism of robinson annilation

Posted by Ayush Parija 7 years, 2 months ago

CBSE > Class 12 > Chemistry

4 answers

We Ayush 7 years, 2 months ago

Thanks

0Thank You

G K 7 years, 2 months ago

Phys : SL Arora....chem : GRB....Math : RD Sharma + cengage + Resonance modules.....NCERT also for all....

0Thank You

Ayush Parija 7 years, 2 months ago

Thank you

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G K 7 years, 2 months ago

It combines two reactions : ...?the Michael Addition?... and the ...?Aldol Condensation?.....MECHANISM : 1st step in the process is the Michael Addition to an α,β-unsaturated ketone, such as methyl vinyl ketone.....then tautomarization occur.....then aldol Condensation rxn ho jayegi....and then finaly 6 membered ring is formed....which is our desired product.....

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ANSWER

How does the presence of double bonds in rubber molecules influence their structure and reactivity?

Posted by Aayush Kaushal 7 years, 2 months ago

CBSE > Class 12 > Chemistry

0 answers

ANSWER

What is mean by fuel cell ? Explain it's working mechanism and also mention it's advantages.

Posted by Tushar Kanojia 7 years, 2 months ago

CBSE > Class 12 > Chemistry

1 answers

Yogita Ingle 7 years, 2 months ago

A fuel cell is a device that produces electricity through a chemical reaction between a source fuel and an oxidant. The source fuel could be almost anything that can be oxidized, including hydrogen, methane, propane, methanol, diesel fuel or gasoline. The only byproducts are water and a small amount of nitrous oxide if air is used as the oxidizer.
Fuel cells offer several advantages over conventional power sources. These include:

Reduced dependence on fossil fuels
Long useful life
High efficiency
Relative safety
Essentially zero toxicity
Minimal maintenance costs

2Thank You

ANSWER

The first ionization enthalpy of 15th group element is higher than 16th group element. Why?

Posted by Yash Surya 7 years, 2 months ago

CBSE > Class 12 > Chemistry

2 answers

Nuke 7 years, 2 months ago

Because 15 group elements have a stable half filled electronic configuration they hardly loose electrons.ie low ionisation enthalpy. But the 16 group elements need to loose only one electron to attain half filled electronic configuration so yhey are ready to loose electrons ie high ionisation enthalpy.

1Thank You

Anjana Sherawat 7 years, 2 months ago

Because of highly stable half field electron configuration

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ANSWER

Why do atom need 8 electrons to be stable and not 5,3, 7 or even 2 electrons

Posted by Jyoti Suntha 7 years, 2 months ago

CBSE > Class 12 > Chemistry

2 answers

Mohit Sepat 7 years, 2 months ago

Not only 8 some also need 16 or 32 eletron to complete their octet .it is depend on shell of electron and the element

1Thank You

Anjana Sherawat 7 years, 2 months ago

Depend on shell and no. of orbital

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ANSWER

sodium nitrate ko ghar par kaise banaye

Posted by Praveen Patel 7 years, 2 months ago

CBSE > Class 12 > Chemistry

2 answers

Princesses Kaur 7 years, 2 months ago

Experiment krke????eetna be nhi pata

1Thank You

Himanshi Monu 7 years, 2 months ago

I dont know

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ANSWER

What do you understand by 'Symbiotic Nitrogen Fixation'? And which two protein are involved in symbiotic nitrogen fixation?

Posted by Bhavya Jain 7 years, 2 months ago

CBSE > Class 12 > Chemistry

0 answers

ANSWER

Why H2o is liquid and H2S is a gas

Posted by Aman Rawat 7 years, 2 months ago

CBSE > Class 12 > Chemistry

2 answers

Himanshi Monu 7 years, 2 months ago

Due to presence of double and single bonds

0Thank You

Bhavya Jain 7 years, 2 months ago

For introduction , this question was put up in "Senior Secondary Examination, 2018 affilited to RBSE. Ans- Water molecules undergo association due to the presence of hydrogen bonding And so H2o is a liquid. Since there is no hydrogen bonding in H2S and so it is a gas.

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ANSWER

???Why nitrogen is found in gaseous state. ❓❔❓❔

Posted by Yo Yo Honey Singh ? 7 years, 2 months ago

CBSE > Class 12 > Chemistry

2 answers

Princesses Kaur 7 years, 2 months ago

Yes 8t ans deep

1Thank You

Deepak Prakash 7 years, 2 months ago

Because two atoms of nitrogen combine with triple bond to form n2 molecule which is very inert and thereby doesnot polymerise to make large molecule. Therefore, nitrogen is found as a gas.

2Thank You

ANSWER

???Ammonia is more basic than phosphine. why❔❓❔❓

Posted by Yo Yo Honey Singh ? 7 years, 2 months ago

CBSE > Class 12 > Chemistry

2 answers

Princesses Kaur 7 years, 2 months ago

This ans is also right deep

1Thank You

Deepak Prakash 7 years, 2 months ago

In ammonia, nitrogen being more electronegative and of small size keeps lone pair more close to it but in phosphine lone pair is not close to that extent, so electron density is higher near nitrogen in ammonia which makes it easier to donate and hence it makes ammonia more basic than phosphine

2Thank You

ANSWER

What is SHE.

Posted by Aman Shukla 7 years, 2 months ago

CBSE > Class 12 > Chemistry

4 answers

Aayush Kaushal 7 years, 2 months ago

Standard hydrogen electrode.....

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G K 7 years, 2 months ago

1Thank You

Deepak Jindal 7 years, 2 months ago

Standard Hydrogen Electrode....?????

0Thank You

G K 7 years, 2 months ago

Standard hydrogen electrode....

4Thank You

ANSWER

Why S is exist as dimagenetic

Posted by Prachi Saxena 7 years, 2 months ago

CBSE > Class 12 > Chemistry

1 answers

Rohit Kumar 7 years, 2 months ago

because S does not have unpaired electron. S is also exist as paramagnetic in the form of S2

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ANSWER

Three dimension packing of Coordination no.

Posted by Abhay Singh 7 years, 2 months ago

CBSE > Class 12 > Chemistry

1 answers

G K 7 years, 2 months ago

I think 12....

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ANSWER

What is the geometical isomer of [Pt(en)2Cl2]2+

Posted by Rahul Singh 7 years, 2 months ago

CBSE > Class 12 > Chemistry

1 answers

Sumit Kumar 7 years, 2 months ago

Cis. And trans both

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ANSWER

What is annealing of glass in chapter-solid state????

Posted by Rajat Dhull 7 years, 2 months ago

CBSE > Class 12 > Chemistry

2 answers

Aniket Upadhyay 7 years, 2 months ago

Rapid cooling and heating up of glass for long time

2Thank You

Aisha Gupta 7 years, 2 months ago

To relieve stresses which will lead to breakage of glass at room temp it is nessary to cool glass in a controlled manner through a predetermined temp gradient.......this controlled process for cooling glass to relieve interior stress is called annealing of glass.

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ANSWER

How can we prepare for jee mains

Posted by Naveen Takshak 7 years, 2 months ago

CBSE > Class 12 > Chemistry

1 answers

Sagar Yadav 7 years, 2 months ago

Hello Naveen you can better prepare... There are many courses which are free of cost on unacademy app me too have done and have great benefits i am sure your confusion will erode away

3Thank You

ANSWER

How can we learn organic question

Posted by Naveen Takshak 7 years, 2 months ago

CBSE > Class 12 > Chemistry

3 answers

Himanshi Monu 7 years, 2 months ago

Read your class notes and solve numericals which i never done

1Thank You

Aniket Upadhyay 7 years, 2 months ago

Understand the concepts

2Thank You

Rajat Dhull 7 years, 2 months ago

Read NCERT and its questions very carefully. No one can stop u to get succeed.

2Thank You

ANSWER

Define covalency

Posted by Mohit Sepat 7 years, 2 months ago

CBSE > Class 12 > Chemistry

1 answers

Anjana Sherawat 7 years, 2 months ago

No. Of electrons shared by an atom in a covalent bonding

3Thank You

ANSWER

How to distinguish b/w order of reaction? Actually i know its a very easy quesbut i am having in analyzing zero order reaction. So please help me guys??

Posted by Muskan Garg 7 years, 2 months ago

CBSE > Class 12 > Chemistry

3 answers

Mohit Sepat 7 years, 2 months ago

By their units .

1Thank You

Nitish Sharma 7 years, 2 months ago

Derive a Relation for 'n'th order of reaction and then eqaute it with dc/dt...u will get the units of the order of reaction for any value of n......

1Thank You

G K 7 years, 2 months ago

By units...

2Thank You

ANSWER

Electrolytic cell

Posted by Sajan Jha 7 years, 2 months ago

CBSE > Class 12 > Chemistry

1 answers

Mohit Sepat 7 years, 2 months ago

Convert electrical energy into chemical energy .the redox process will spontaneous. And responsible for production of electrical energy .

1Thank You

ANSWER

Explain sterric hindrance

Posted by Kanchan Chauhan 7 years, 2 months ago

CBSE > Class 12 > Chemistry

1 answers

Aniket Upadhyay 7 years, 2 months ago

Crowding due to large groups

2Thank You

ANSWER

Why is sulphuric acid not used during the reavtion of alcohols with kI

Posted by Rafiuddin Khan 7 years, 2 months ago

CBSE > Class 12 > Chemistry

2 answers

Muskan Garg 7 years, 2 months ago

A very perfect and limited answrr.. impressive?

1Thank You

Anjana Sherawat 7 years, 2 months ago

It changes HI into I2 so iodine is not free to react with alcohol

1Thank You

ANSWER

What are azeotropes ❓❔❓

Posted by Yo Yo Honey Singh ? 7 years, 2 months ago

CBSE > Class 12 > Chemistry

3 answers

Deepak Jindal 7 years, 2 months ago

?????

0Thank You

Aayush Kaushal 7 years, 2 months ago

A mixture of two liquids which has a constant boiling point and composition throughout distillation.

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Deepak Jindal 7 years, 2 months ago

It is mixture of two or more liquids whose proportions cannot be altered.

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ANSWER

BiH3 is the strongest reducing agent among all the hydrides of the hydrides of group 15 elements. WHY❔❓

Posted by Yo Yo Honey Singh ? 7 years, 2 months ago

CBSE > Class 12 > Chemistry

2 answers

Aayush Kaushal 7 years, 2 months ago

Because as we move down the group the stability decreases and due to which reducing capacity increases .

2Thank You

Anjana Sherawat 7 years, 2 months ago

The bond length of Bi and H bond is maximum in15 group hydrides so this bond can easily break down and can give a H+ ion .so it is strongest reducing agent

1Thank You

ANSWER

Define Chelation ❓❔❓❔

Posted by Yo Yo Honey Singh ? 7 years, 2 months ago

CBSE > Class 12 > Chemistry