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What is positive and negative deviations?explain.

Posted by Kashish Rana 6 years, 8 months ago

4 answers

Akarsh Gupta 6 years, 8 months ago

Experiment krne pr agr solution kii heat enthalpy,volume ,interaction etc kii values greater than 0 aaye to positive deviation hoga

1Thank You

Priya Ravi 6 years, 8 months ago

Positive can be also understand by...this...if vapour pressure of the solution..will be more than the pure solvent that mean there is positive deviation take place..

0Thank You

Kashish Rana 6 years, 8 months ago

Ye hi to smj ni aara

0Thank You

Balraj Singh 6 years, 8 months ago

Positive devition are those in which A-B intrection is higher than the A-A and B-B intreciton

1Thank You

ANSWER

How can i prepare solutions chapter in one night because tommorow my test of chemistry ch-solution will be taken.,..?????????pls jaldi bta do

Posted by ???. Pragati 6 years, 8 months ago

CBSE > Class 12 > Chemistry

3 answers

Aman Kumar 6 years, 8 months ago

Avni....yar don't take stress?as u know last time mai sab padna bewokuffi hai...just study that topic which uh feel important...and remember...ki konse topic ko tumhare teacher importantly padhaye hai ussi ko padho .....time nhi hai .........so kuch na hone se acha , ki kuch toh ho....u got it..what i mean to say

1Thank You

∂Αяѕнαиαα ყα∂Αѵ ??? 6 years, 8 months ago

baaki opper wale ki rehmat hai... ✌️?

0Thank You

∂Αяѕнαиαα ყα∂Αѵ ??? 6 years, 8 months ago

no idea it's vast... but last minute preparation include jinna aapko aata hai utna cover ker lo and ncert kar lena...

0Thank You

ANSWER

is,it good learn whole ncert word by word of chemistry?

Posted by Tirthesh Jain 6 years, 8 months ago

CBSE > Class 12 > Chemistry

4 answers

∂Αяѕнαиαα ყα∂Αѵ ??? 6 years, 8 months ago

Parishek bhai mai bhen hoon.... It's Darshana ( दर्शाना) ..... hope u understand...

2Thank You

Aman Kumar 6 years, 8 months ago

Ye baat 110% such hai....hamare teacher bolte the ki...ncert ka ek bhi line miss ho gya ager...that means u have lost ur 1 marks

1Thank You

Tirthesh Jain 6 years, 8 months ago

thank you bhai

1Thank You

∂Αяѕнαиαα ყα∂Αѵ ??? 6 years, 8 months ago

it's not good it's best... NCERT by heart kerna means we are able to score above 90+ in cbse board exam.

2Thank You

ANSWER

What is the Simple meaning of mole fraction?

Posted by Parvathi G Nair 6 years, 8 months ago

CBSE > Class 12 > Chemistry

2 answers

Yogita Ingle 6 years, 8 months ago

Mole fraction can be defined as the ratio of number of moles of the component in the solution to the total number of moles of all components in the solution.
It is denoted by the alphabet x and subscript written on the right hand side of x denotes the component of which mole fraction is being calculated.
Mathematically, Mole fraction of a component =number of moles of the component / total number of moles of all components

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Nidhi Verma 6 years, 8 months ago

Mole of one component /mole of total component

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ANSWER

Henry's law is too long ,which one should be written if it comes in test?

Posted by Nidhi Verma 6 years, 8 months ago

CBSE > Class 12 > Chemistry

5 answers

Aman Kumar 6 years, 8 months ago

Esmai predend karne ki baat nhi.....ab koi baat nhi karega toh...aisa hi question nikle ga na mind se???

0Thank You

∂Αяѕнαиαα ყα∂Αѵ ??? 6 years, 8 months ago

why are **

1Thank You

∂Αяѕнαиαα ყα∂Αѵ ??? 6 years, 8 months ago

? ? ? tumhe kya ho gaya.... why pretending like bahut Dino ke baad mill re hoo... by the way...___study bus chl ri hai 60 ki speed se... ✌️.. what about u???

1Thank You

Aman Kumar 6 years, 8 months ago

Kaisi hai..darsh...how's ur study?

0Thank You

∂Αяѕнαиαα ყα∂Αѵ ??? 6 years, 8 months ago

Go through with this definition if u feel it easy....___ Henry's law states that the partial pressure of the gas in vapour phase is directly proportional to the mole fraction of the gas in the solution.

5Thank You

ANSWER

Tell me plzz .Why fish will feel more comfortable in cold water as compared to hot water?

Posted by Lakhan Ram 6 years, 8 months ago

CBSE > Class 12 > Chemistry

1 answers

Priya Dharshini ? 6 years, 8 months ago

Cold water has more dissolved oxygen than warm water. This the reason why aquatic animals are more comfortable in cold water than warm water. Amount of dissolved oxygen decreases with temperature increases .... this may be correct....

2Thank You

ANSWER

Explain normality

Posted by Yuvraj Singh 6 years, 8 months ago

CBSE > Class 12 > Chemistry

1 answers

Nidhi Verma 6 years, 8 months ago

It is defined as no.of gram equivalent in 1 lit of solution

1Thank You

ANSWER

Why glass rod contains positive charge, why not negative charge?

Posted by Rishita Shishir ?✏ 6 years, 8 months ago

CBSE > Class 12 > Chemistry

1 answers

Uday Mann 6 years, 8 months ago

When a glass rod is rubbed with silk, electrons are transferred from the glass rod to the silk. Since the glass rod losses electrons, it becomes rich in positive charge. Similarly, the silk cloth becomes negatively charged

4Thank You

ANSWER

Mole fraction of glucose in a solution of which has a solvent of molecular mass 25 0.2 and density of solution is 1.4 gram per ml cube then calculate the molarity of the solution

Posted by Mayank Chobey 6 years, 8 months ago

CBSE > Class 12 > Chemistry

1 answers

Mayank Chobey 6 years, 8 months ago

Viray

0Thank You

ANSWER

Explain why alkyl halides are generally not prepared in the laboratory by free radical halogenation of alkanes???....

Posted by ∂Αяѕнαиαα ყα∂Αѵ ??? 6 years, 8 months ago

CBSE > Class 12 > Chemistry

6 answers

Aman Kumar 6 years, 8 months ago

Hey, darshana...I know tum bhi block ho gyi ho...soo ager tum chaho toh....dusre account (jo account block nhi hai wo) se wapas aa sakti ho... Or email id wala plan...bhi proceed kar sakte hai..becoz I don't have fb....otherwise...koi nhi...phir ek month baad ...If u feel this idea appropriate then..give me thanks or ager tumhe thoda bhi doubt ho ess idea k bare mai then I will not mind?... strictly don't .....give me thanks....?

1Thank You

Priya Dharshini ? 6 years, 8 months ago

Ur wlcm aman,darshana....

2Thank You

Nishu Sahu 6 years, 8 months ago

Because it is not good way as most of the product formed during halogenation so separation of required product become difficult. e.g. chlorination of methane gives CH3Cl,. CH2Cl2, CHCl3,. CCl4.

1Thank You

Aman Kumar 6 years, 8 months ago

Nice explaination priya?

1Thank You

∂Αяѕнαиαα ყα∂Αѵ ??? 6 years, 8 months ago

thx a lot yarr . ☺️ ✌️

2Thank You

Priya Dharshini ? 6 years, 8 months ago

THE CARBON OXYGEN BOND IN PHENOYL HAVE A PARTIAL DOUBLE BOND CHARACTER AND IT IS DIFFICULT TO BREAK. .....

3Thank You

ANSWER

Why polymers are unstable at higher temperature?

Posted by Shweta Sonkar 6 years, 8 months ago

CBSE > Class 12 > Chemistry

3 answers

Ayush Kumar Singh 6 years, 8 months ago

Polymer ka

0Thank You

Uday Mann 6 years, 8 months ago

Higher temperature processes are the result of thermal cleavage of bonds in the polymer backbone. ... For some polymers degradation is initiated from the endgroups so that end-capped polymers may be more stable than those that have reactive chain ends.

0Thank You

Priya Dharshini ? 6 years, 8 months ago

Which chapter ???

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ANSWER

the electrical conductivity of metal decreases with temprature while that of semiconductor increases . explain?

Posted by Navdeep Kaur 6 years, 8 months ago

CBSE > Class 12 > Chemistry

0 answers

ANSWER

why a bottle of nail enamel remover is suggested to be kept in refrigerator during summer?

Posted by Disha Gupta 6 years, 8 months ago

CBSE > Class 12 > Chemistry

3 answers

Priya Dharshini ? 6 years, 8 months ago

This may be correct beacuse in reality when we open a nail polish remover it evaporates fast sublimation wat u call it. So thats the reason it may be kept in refrigerators...

0Thank You

Kumar Vishal Behera 6 years, 8 months ago

But i may not be correct so sorry for that if its wrong ans

1Thank You

Kumar Vishal Behera 6 years, 8 months ago

I don't know the exact answer but may be its a volatile substance so it will evaporate faster due to high temperature in summer.

1Thank You

ANSWER

A solution of glucose in water is labelled as 10percent w/w,what would be the molality and mole fraction of each component in the solutions?if the density of solution is 1.2g/ml, then what shall be the molarity of the solution?

Posted by Gaurav Kumar 6 years, 8 months ago

CBSE > Class 12 > Chemistry

3 answers

Ayushi Ayushi 6 years, 8 months ago

Welcome

1Thank You

Aman Kumar 6 years, 8 months ago

Nice explained...?thanks

1Thank You

Ayushi Ayushi 6 years, 8 months ago

10% w/w solution of glucose in water means that 10 g of glucose in present in 100 g of the solution i.e., 10 g of glucose is present in (100 - 10) g = 90 g of water. Molar mass of glucose (C6H12O6) = 6 × 12 + 12 × 1 + 6 × 16 = 180 g mol - 1 Then, number of moles of glucose= 90÷180 = 0.056 mol Molality of solution = 0.056×1000 ÷90=0.62 Number of moles of water=90÷18 = 5 mol Mole fraction of glucose= 0.056÷0.056 +5=0.011 And, mole fraction of water = 1 - 0.011 = 0.989 If the density of the solution is 1.2 g mL - 1 , then the volume of the 100 g solution can be given as: 100÷1.2=83.33 m/l = 83.33×10^-3 Molarity of the solution =0.056÷83.33×10^-3=0.67

2Thank You

ANSWER

3D packing in cubic packing

Posted by Sumit Rawat 6 years, 8 months ago

CBSE > Class 12 > Chemistry

0 answers

ANSWER

Ch 2

Posted by Anshul Chauhan 6 years, 8 months ago

CBSE > Class 12 > Chemistry

1 answers

Kislay Kumar 6 years, 8 months ago

What's your question?? Ch 2 chemistry, but what do you want from it ??

0Thank You

ANSWER

What is volatile and non volatile solution.?

Posted by Anjali Roy 6 years, 8 months ago

CBSE > Class 12 > Chemistry

2 answers

Hritik Kumar 6 years, 8 months ago

Volatile substance are those substance which evaporate easily and non volatile do not escape ex h2o , c6h6,c2h5oh etc

1Thank You

Manika Gupta 6 years, 8 months ago

Volatile are those substances that forms vapour and nonvolatillle does not form vapour

3Thank You

ANSWER

Formet of practicle

Posted by Chetna Sahu 6 years, 8 months ago

CBSE > Class 12 > Chemistry

0 answers

ANSWER

Is book modern abc + is good to crack board chemistry .?

Posted by Saini Simran 6 years, 8 months ago

CBSE > Class 12 > Chemistry

5 answers

Kislay Kumar 6 years, 8 months ago

No book is ideal to crack any kind of exam. You only need is to build up concepts stronger and practise more and more on that. But every exam,NCERT books gives you all informations at a glance in very short so you have to study them in detail by yourself also its questions provides you every kind of applications of conceptual questions. Finally, follow only one book blindly and for reference you may use any book and be focused in your syllabus as issued in ncert.

2Thank You

Priya Dharshini ? 6 years, 8 months ago

It is good for board exam...

0Thank You

Aman Kumar 6 years, 8 months ago

Yah....for board ncert is best...but on the other side, both pradeep and modern abc is nice...but according to me....modern abc is more appropriate???

0Thank You

∂Αяѕнαиαα ყα∂Αѵ ??? 6 years, 8 months ago

yup it's best...bohot sahi.. ✌️... but if we practice each and every question.

1Thank You

Nishu Sahu 6 years, 8 months ago

I think pradeep is better than modern abc and for board u should focus more on ncert.

0Thank You

ANSWER

A solution prepared by dissolving 1.25g of oil of winter green (methyl salicylate )in 99g of benzene has a boiling point of 80.31 determine the malar mass of this cimpound (B.P of pure benzene =80.10 and kb for benzene=2.53kg mol

Posted by Sagar Indora 6 years, 8 months ago

CBSE > Class 12 > Chemistry

4 answers

Aman Kumar 6 years, 8 months ago

Just kidding....nicely explained thanks??

0Thank You

∂Αяѕнαиαα ყα∂Αѵ ??? 6 years, 8 months ago

Teri shkl kyu bann gyi... ? ?... vese mess ho gaya... ?... maine tareeke se likha tha... ? ?

1Thank You

∂Αяѕнαиαα ყα∂Αѵ ??? 6 years, 8 months ago

hope u will understand... ??

0Thank You

∂Αяѕнαиαα ყα∂Αѵ ??? 6 years, 8 months ago

given ➡️ Tb=80.31°C, ➡️Tb° = 80.10°C,,, ➡️Kb =2.53°C kgmol^-1. ✴️ δT = Tb - Tb° =80.13°C - 80.10°C = 0.21 °C δTb =kb ×1000 ×w2 /M2 ×w1..._____(1) M2 =kb×1000 ×w2 /δTb ×w1.. =2.53×1000×1.25/0.21°C ×99. =152.11 ×10³ g/mol.

2Thank You

ANSWER

Is electrophilic substitution from the first chapter deleted from the sullabus?

Posted by Aiswarya Vilasini 6 years, 8 months ago

CBSE > Class 12 > Chemistry

3 answers

Priya Dharshini ? 6 years, 8 months ago

No... it is not deleted it is there

1Thank You

Aman Kumar 6 years, 8 months ago

No...it is there

2Thank You

∂Αяѕнαиαα ყα∂Αѵ ??? 6 years, 8 months ago

No it is in the syllabus..

4Thank You

ANSWER

which is the best book for last year papers

Posted by Priya Sharma 6 years, 8 months ago

CBSE > Class 12 > Chemistry

4 answers

Jashan Sethi 6 years, 8 months ago

Only ncert will help you score more than 90%

2Thank You

Yash Sharma 6 years, 8 months ago

Arihant

2Thank You

Priya Sharma 6 years, 8 months ago

1Thank You

Aman Kumar 6 years, 8 months ago

Arihant

2Thank You

ANSWER

What is grignard reaction

Posted by Sanjay Kumar 6 years, 8 months ago

CBSE > Class 12 > Chemistry

1 answers

Yogita Ingle 6 years, 8 months ago

Grignard reagents: Alkyl magnesium halides (RMgX) are called Grignard reagents.
Preparation of Grignard reagents: When a solution of alkyl halide (R—X) in ether is allowed to stand over magnesium turning for some time then metal gradually dissolves. In this reaction alkyl magnesium halide is formed. This compound is called Grignard reagent.
R-X + Mg {tex}\xrightarrow{dry\;ether}{/tex} R-Mg-X

2Thank You

ANSWER

What is difference between osmosis and osmotic pressures

Posted by Vanya Singh 6 years, 8 months ago

CBSE > Class 12 > Chemistry

2 answers

Jashan Sethi 6 years, 8 months ago

The external pressure applied on solution side to prevent or stop the process of osmosis . Whereas osmosis is the process in which solvent particles flow from the solution of low concentration to the solution of high concentration

1Thank You

Yogita Ingle 6 years, 8 months ago

Osmotic pressure is the pressure that we need to apply to stop the flow of solvent molecules from a dilute solution to a concentrated solution through a semi-permeable membrane. Now, the above statement has many terms that need a thorough explanation.
We have observed that when we separate a dilute solution from a concentrated solution of the same type by a membrane, the solvent molecules flow from the dilute solution to the concentrated solutions. This movement continues until it reaches an equilibrium. This process of flow of solvent molecules due to the difference in concentration is osmosis.

1Thank You

ANSWER

Kf for water is 1.86 k kg mol if your auto mobile radiator holds 1 kg of water who many grams of ethelene lic (c2H6O2) must you add 2 gete the freezing point of the solution lower to -2.8 c

Posted by Shashank Rathore 6 years, 8 months ago

CBSE > Class 12 > Chemistry

0 answers

ANSWER

Conversion of formic acid to acetic acid

Posted by Madhvi Tiwari 6 years, 8 months ago

CBSE > Class 12 > Chemistry

2 answers

Yogita Ingle 6 years, 8 months ago

Step-1. Formic acid may be reduced to methanol by reacting it with lithium aluminium hydride.
2. Methanol on reaction with PCl₅ or SOCl₂ will give methyl chloride.
CH₃OH + SOCl₂ = CH₃Cl + HCl + SO₂
3. Methyl chloride on reaction with KCN will form CH₃CN, which on hydrolysis yields acetic acid.

3Thank You

Shashank Rathore 6 years, 8 months ago

Ethical issues to freezing point

2Thank You

ANSWER

What are ambident nucleophiles? Explain wit an exampl.

Posted by Sandeep Yadav 6 years, 8 months ago

CBSE > Class 12 > Chemistry

3 answers

Sandeep Yadav 6 years, 8 months ago

0Thank You

Yogita Ingle 6 years, 8 months ago

Ambident nucleophiles: The nucleophiles with two nucleophilic centres are called ambident nucleophile.For example cyanide act as ambident nucleophilies.
There are two nucleophiles centres, at carbon and nitrogen in cyanide ion (C ≡ N:). They can react through either of these centres. Depending on the reagent and the reaction conditions, the reaction may take place predominantly at one of these centres.

1Thank You

Avantika Tayal 6 years, 8 months ago

Nucleophiles having 2 point of linkage.eg:CN;NC ,

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ANSWER

How much marks numericals came in chemistry 12 class. CBSE

Posted by Jas Aulakh 6 years, 8 months ago

CBSE > Class 12 > Chemistry

2 answers

∂Αяѕнαиαα ყα∂Αѵ ??? 6 years, 8 months ago

it's not fix.... every year they use to change the statistics... but observation said approx 8 marks or might be 10 marks.

3Thank You

Suraj Kumar 6 years, 8 months ago

How much marks numericals came in chemistry 12 class. CBSE

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ANSWER

Dehalogenation of meso-2,3,-dibromobutane results in__________???

Posted by ∂Αяѕнαиαα ყα∂Αѵ ??? 6 years, 8 months ago

CBSE > Class 12 > Chemistry

9 answers

∂Αяѕнαиαα ყα∂Αѵ ??? 6 years, 1 month ago

thanks

0Thank You

∂Αяѕнαиαα ყα∂Αѵ ??? 6 years, 3 months ago

0Thank You

Aman Kumar 6 years, 8 months ago

Ofcourse,??

0Thank You

∂Αяѕнαиαα ყα∂Αѵ ??? 6 years, 8 months ago

arrey Sirf organic he mtt keriyo... baaki chapters v hai.... pta Chale examination mein mujhe mann he mabn the bole ulti advice DE di..... ? ? ? ?.... physical chem v ker liyo... ? ?

1Thank You

Aman Kumar 6 years, 8 months ago

But really....thanks a lot...I feel ur answer very helpful....khas hum baat kar pate ? ....but sayad possible nhi....but..thanks for the help yara?

1Thank You

Aman Kumar 6 years, 8 months ago

That means ,, mai 12th class k organic ko hi karu...na....?

1Thank You

∂Αяѕнαиαα ყα∂Αѵ ??? 6 years, 8 months ago

conversion hai vo ***

2Thank You

∂Αяѕнαиαα ყα∂Αѵ ??? 6 years, 8 months ago

deekh koi rocket science ni hai ismay chill ho ke ker sub.... phale NCERT ko udda.... NCERT ki ek ek chemical equation ko dimag may chaap le.... baad may NCERT ke he questions per strike ker kyuki organic may direct mechanism aati hai ya conversation Jo ncert se he li jaati hai aur jub tujhe lge tu James bond baan gaya then pradeep ka encounter ker de.... ?

3Thank You

∂Αяѕнαиαα ყα∂Αѵ ??? 6 years, 8 months ago

Mujhe organic he aati hai physical chem bahut km.... aur best part ye hai ke meri teacher ne 2nd book phale start ker di.... ? ? ?... kismat saath chl ri hai avi... ? ?

3Thank You

ANSWER

Is cathode negative or positive ???

Posted by Appy Garnara 6 years, 8 months ago

CBSE > Class 12 > Chemistry