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What is electro dispersion

Posted by Abhishek Kadela 7 years ago

CBSE > Class 12 > Chemistry

0 answers

ANSWER

why chemistry is not undertandable?

Posted by Nikhil Koundal 7 years ago

CBSE > Class 12 > Chemistry

3 answers

Nikhil Koundal 7 years ago

but from last 4 days i have completed. 6 chapters with full patience and understanding but today when i used revise them again, all the concepts were clear from my mind, so why is this happened?

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Suhani Rana? 7 years ago

Because you think every thing is out of syllabus??

1Thank You

Adarsh Deep Gupta 7 years ago

Because it is tricky subject......chemistry is not hard.If u study with patience then it is helpful for you.

1Thank You

ANSWER

What is the Molicular base of inheritance

Posted by Ashique Ashique 7 years ago

CBSE > Class 12 > Chemistry

2 answers

Shivam Jaiswal 7 years ago

Bhau ha quesgion bio cha ahe pahele chemestry wach mag bio pahu Molecular genetics is known as molecular basis of inheritance chapter cha nav ahe

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Nikhil Koundal 7 years ago

ask questions from syllabus plzzz.

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What is anomeric carbon?????

Posted by Nishat Shabnam 7 years ago

CBSE > Class 12 > Chemistry

1 answers

Suhani Rana? 7 years ago

The two cyclic hemiacetal structure of glucose differ only in the configuration of -OH group at first carbon also known as anomeric carbon and two isomers i.e alpha-D-(+)-glucose and beta-D-(+)-glucose are known as anomers

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ANSWER

is there any change in syllabus for 18-19??? and also is there any change in question paper format??

Posted by Dharshika As 7 years ago

CBSE > Class 12 > Chemistry

2 answers

Shivam Jaiswal 7 years ago

2 more 2 marks que

1Thank You

Shivam Bhati 7 years ago

No value based question

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ANSWER

What is polymorphs

Posted by Raj Kumar 7 years ago

CBSE > Class 12 > Chemistry

1 answers

Aryan Baliyan 7 years ago

The diffrent crystalline form of the substance is called polymorphs.

1Thank You

ANSWER

Why does no2 demerises

Posted by Abhishek Nanda 7 years ago

CBSE > Class 12 > Chemistry

1 answers

Akash Akash 7 years ago

It has odd number of valence electrons

3Thank You

ANSWER

If we are to answer that why does PH4+ has greater bond angle than PH3 .....how are we supposed to explain this from boards point of view

Posted by Prakriti Mehta 7 years ago

CBSE > Class 12 > Chemistry

1 answers

Suhani Rana? 7 years ago

There is lone pair in PH3 which causes lone pair bond-pair repulsion and reduces its bond angle to 93.6° and in PH4+ there is no lone pair hence there is no lone pair-bond pair repulsions so the angle is 109.5 which is gteater than in PH3

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Sir please tell whether the chapter 'the solid state' is removed from the syllabus or not

Posted by Shubham Singh Singh 7 years ago

CBSE > Class 12 > Chemistry

2 answers

Shivam Keshri 7 years ago

No sir it isnt removed?

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Shreya Singh 7 years ago

no it's their.

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Difference between ideal and non ideal solution ?

Posted by Preetibardhan Panda 7 years ago

CBSE > Class 12 > Chemistry

4 answers

Shivam Jaiswal 7 years ago

P.n 45 and 46 ncert part 1

1Thank You

Aryan Baliyan 7 years ago

For ideal solution- 1.Theortial pressure =Observed pressure 2.They follow Rault's law 3.∆H=0 4.∆P=0 5.A-A+B-B=A-B For non ideal solution- 1.Theortical pressure does not equal to Observed pressure. 2.They do not follow Rault's law. 3.∆H does not equal to 0. 4.∆P does not equal to 0. 5.A-A+B-B bond does not equal to A-B bond.

1Thank You

Prakriti Mehta 7 years ago

*over the entire range of. Concentration

1Thank You

Harshil Thakar 7 years ago

Ideal solution follows raoults law amd non ideal solution doesnt follow raoults law

3Thank You

ANSWER

Is this year any change is question paper like marking scheme, no. of choices,etc?

Posted by Chetan Yadav 7 years ago

CBSE > Class 12 > Chemistry

2 answers

Sahana Sankaranarayanan 7 years ago

This is for 2018-19

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Sahana Sankaranarayanan 7 years ago

Value based question which was of 4 marks has been removed and no of choices has been increased

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Define kohlrausch law

Posted by Sangeeta Nara 7 years ago

CBSE > Class 12 > Chemistry

1 answers

Yogita Ingle 7 years ago

The Kohlrausch law states that : "At infinite dilution, when dissociation is complete, each ion makes a definite contribution towards equivalent conductance of the electrolyte irrespective of the nature of the ion with which it Is associated and the value of equivalent conductance at infinite dilution for any electrolyte is the sum of contribution of its constituent ions"

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How can we get root of a number in log ??

Posted by Cicil George 7 years ago

CBSE > Class 12 > Chemistry

2 answers

Sahana Sankaranarayanan 7 years ago

For eg say you have to find log(root 2) Root 2 can be written as 2^1/2 Log (2^1/2) One property of logarithms say that log (a^m) = m log a Applying this property 1/2 log 2 Log 2 = 0.3010 Finaly answer will be 1/2 × 0.3010= 0.1505

0Thank You

Shivam Keshri 5 years, 11 months ago

By using calculator?

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calculate the vapour pressure of an aqueous solution containing five percent by mass यूरिया एन एक्स conh2 at 298 Kelvin the pressure of water at 298 kelvin is 23.75 mm of HG give the answer

Posted by Abhinav Raj 7 years ago

CBSE > Class 12 > Chemistry

0 answers

ANSWER

calculate the vapour pressure of an aqueous solution containing five percent by mass urea NH2 co NH2 and H2 at 298 Kelvin the vapour pressure of water at 298 kelvin is 23.75 mm of HG

Posted by Abhinav Raj 7 years ago

CBSE > Class 12 > Chemistry

0 answers

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NF3 is an exothermic compound whereas NCl3 is not...why???

Posted by Shivam Keshri 7 years ago

CBSE > Class 12 > Chemistry

2 answers

Suhani Rana? 7 years ago

This is due to lower bond dissociation enthalpy of F2 and comparable size of nitrogen and fluorine when NF3 is formed energy is released hence it is an exothermic compound.however NCl3 is endothermic compound due to high bond dissociation enthalpy of Cl2.

2Thank You

Sahana Sankaranarayanan 7 years ago

The enthalpy of formation of NCl3 is due to the large size difference of N and Cl atoms as N belongs to second period and Cl belongs to the third period making the N-Cl bond weak, whereas in NF3, since both the atoms belongs to the second period & are small in size therefore N-F bond is strong making it exothermic.

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ANSWER

The element of 3d transition series are Sc Ti V Cr Mn Fe Co Ni Cu Zn (i) write the element ehich show maximum no. Of oxidation state give reasons. (ii). Highest melting point (iii). Show only +3 oxidation state (iv). Strong oxidising agent in +3 oxidation state and why?

Posted by Sãñjü Dïdêl 7 years ago

CBSE > Class 12 > Chemistry

0 answers

ANSWER

cbse new paper pattern question paper of chemistry 2019

Posted by Mahabir Parwala 7 years ago

CBSE > Class 12 > Chemistry

1 answers

Harsha Phansalkar 7 years ago

Value based questions are removed only one change

5Thank You

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Write the equation showing the relationship between equivalent and concentrate of a strong electrolyte..

Posted by Sahana Sankaranarayanan 7 years ago

CBSE > Class 12 > Chemistry

0 answers

ANSWER

Mention the condition required to maximise the yield of ammonia.

Posted by Nishant Mittal 7 years ago

CBSE > Class 12 > Chemistry

1 answers

Suhani Rana? 7 years ago

According to lachetelier's principle to maximise the yield high pressure of 200 atm and low temperature of about 723 k favour the formation of NH3 also small amount of k2O and Al2O3 increases the rate of reaction.

1Thank You

ANSWER

Why is finely divided substance more affective as an adsorbent

Posted by Harsh Sharma 7 years ago

CBSE > Class 12 > Chemistry

2 answers

Nivetha Vijayakumar 7 years ago

Adsortion increases with increase in surface area. When a substance is finely divided, it's surface area increases which increases the adsorption

1Thank You

Snehanshu Senapati 7 years ago

It create more surface area for adsorbtion.

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ANSWER

Is solid state included in class 12 syllabus for session 2019-20

Posted by Monty Hooda 7 years ago

CBSE > Class 12 > Chemistry

4 answers

Nidhish Yadav 7 years ago

Yes

1Thank You

Gargi Sharma 7 years ago

Yes it is

0Thank You

Suhani Rana? 7 years ago

Sorry i think no

0Thank You

Suhani Rana? 7 years ago

Yes?

3Thank You

ANSWER

what is matty

Posted by Gaddam Vijaya 7 years ago

CBSE > Class 12 > Chemistry

2 answers

Komal Tatrari 7 years ago

I believe its copper matty it is a mixture of Cu2S, Cu2O,FeS, FeO which are obainted from reverbaratory furnace after roasting

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Sahana Sankaranarayanan 7 years ago

In which context are you asking this?

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ANSWER

Why we use conical flask for titration

Posted by Shallu Singh 7 years ago

CBSE > Class 12 > Chemistry

1 answers

Muskan Goyal 7 years ago

Because of swirling. Swirling in a conical flask makes the solution run back down properly without splitting out. But in a beaker chances of slashing out of that sample solution is more.

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Plz...anyone tell me important topics in coordination compounds

Posted by Nawal Yadav 7 years ago

CBSE > Class 12 > Chemistry