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What is striochemistry sn1 reaction

Posted by Abhishek Chauhan 6 years, 4 months ago

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A mixture which contain 0.550 g of camphor and 0.045 g of an organic solute freezes at 157 degree Celsius. The solute contains 93.46 % of carbon and 6.54% of H by weight. What is the molecular formula of the compound? (Freezing point of camphor =178.4 degree Celsius and kf=37.70)

Posted by Yuvraj Singh Chauhan 6 years, 4 months ago

CBSE > Class 12 > Chemistry

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Plz tell me the mechanism of CH3-CH=CH2 + HBr in the presence of H2O2

Posted by Afzal Chaudhary 6 years, 4 months ago

CBSE > Class 12 > Chemistry

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Explain why the dipole moment of chlorobenze is lower than that of cyclohexyle chloride

Posted by Virender Rana 6 years, 4 months ago

CBSE > Class 12 > Chemistry

1 answers

Humaira .. 6 years, 4 months ago

Bcz in case of chlorobenzene due to ( - I effect) its stability increases than cyclohexyl chloride. As we know stability is inversely proportional to dipole moment so, its d. P is lower than latter one.

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Alternate current topic is in which chapter

Posted by Lavanns Lavanns 6 years, 4 months ago

CBSE > Class 12 > Chemistry

1 answers

Parul Singh 6 years, 4 months ago

Ch 7

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X:F2C=C=CF2 Y:F2B-C (triple bond) C-BF2 wich of two is impossible for all four aoms to lie in same plane a) X b)Y c) X and Y d) None plz answer with reasons..

Posted by Vasu Yadav 6 years, 4 months ago

CBSE > Class 12 > Chemistry

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why noble gas have low melting point

Posted by Sarthak Pandey 6 years, 4 months ago

CBSE > Class 12 > Chemistry

2 answers

Sia ? 6 years, 4 months ago

Noble gases being monoatomic have no inter atomic forces except weak dispersion forces and therefore, they are liquefied at very low temperatures. Hence, they have low boiling points.

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Sarthak Pandey 6 years, 4 months ago

Thanks sia

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What is the balanced chemical equation for: Chlorine gas is passed into a solution of NaI in water?

Posted by Aradhya Trivedi 6 years, 4 months ago

CBSE > Class 12 > Chemistry

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Order of boiling pt of hydrides of gp 16

Posted by Tannu Madaan 6 years, 4 months ago

CBSE > Class 12 > Chemistry

2 answers

Sia ? 6 years, 4 months ago

The thermal stability of hydrides decreases on moving down the group. This is due to a decrease in the bond dissociation enthalpy (H-E) of hydrides on moving down the group. Therefore,

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Tannu Madaan 6 years, 4 months ago

I asked boiling point

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Why does average rate is not better to measure the rate of reaction?

Posted by Shruti Kaushal ???? 6 years, 4 months ago

CBSE > Class 12 > Chemistry

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Class12 last year paper 2019delhi

Posted by Sandhya Shriwash 6 years, 4 months ago

CBSE > Class 12 > Chemistry

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Sia ? 6 years, 4 months ago

You can check last year papers here : https://mycbseguide.com/cbse-question-papers.html

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The which transition metal

Posted by Sandhya Shriwash 6 years, 4 months ago

CBSE > Class 12 > Chemistry

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Sia ? 6 years, 4 months ago

The 38 elements in groups 3 through 12 of the periodic table are called transition metals.
The Transition Metals are:

Scandium.
Titanium.
Vanadium.
Chromium.
Manganese.
Iron.
Cobalt.
Nickel.

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Board practicals are held in school or at centres

Posted by Anurag Yadav 6 years, 4 months ago

CBSE > Class 12 > Chemistry

5 answers

Priya Dharshini ? 6 years, 4 months ago

NOt yet sure.. but other websites states thst it will be held at our centres..

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Yash Jain 6 years, 4 months ago

At school

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Řøhăň Řąjpůť ✌️✊ 6 years, 4 months ago

at centre bro

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White Rat Hackers ? Ceo 6 years, 4 months ago

At centers

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Anurag Yadav 6 years, 4 months ago

In centres

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Why are powdered substance more effective adsorbents than their crystalline forms

Posted by Mixti Rwt 6 years, 4 months ago

CBSE > Class 12 > Chemistry

1 answers

Gaurav Seth 6 years, 4 months ago

Powdered substances are more effective adsorbents than their crystalline forms because when a substance is powdered, its surface area increases and physisorption is directly proportional to the surface area of the adsorbent.

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Why noble metals doesn't react with o2?

Posted by Sujeet Rangaa 6 years, 4 months ago

CBSE > Class 12 > Chemistry

1 answers

Naman Chauhan 6 years, 4 months ago

Ionization enthlpy is very high and electron gain enthlpy is zero

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Arrange the oxoacids of chlorine according to their- Oxidising power Acidity Stability

Posted by Kalpana Jha 6 years, 4 months ago

CBSE > Class 12 > Chemistry

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Number of electrons required to deposit 1 gram equivalent of aluminium from solution of alcl3 is?

Posted by Soham Repe 6 years, 4 months ago

CBSE > Class 12 > Chemistry

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why is the electron gain enthalpy of oxygen is less than that of sulphur

Posted by Suyash Tripathi 6 years, 4 months ago

CBSE > Class 12 > Chemistry

1 answers

Yogita Ingle 6 years, 4 months ago

The negative electron gain enthalpy is more in sulphur than in oxygen because, both of them are in 16th group in which teh oxygen is 1st element which has the minimum size and sulphur has larger size due to addition of a new shell.
So, due to smaller size the inter-electronic repulsion in compact 2p-orbitals of oxygen is much more than the repulsion in 3p-orbitals of sulphur hence, the incoming new electron feels less attraction in oxygen and more attraction in sulphur due to which the addition becomes easy and so electron gain enthalpy becomes more negative in sulphur.

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Half life of a zero order reaction

Posted by Kiran??? Gautam 6 years, 4 months ago

CBSE > Class 12 > Chemistry

1 answers

Sia ? 6 years, 4 months ago

Half-life (t_1/2) for a zero order reaction, {tex}t_{1 / 2}=\frac{[R]_{0}}{2 k}{/tex}

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Is ncert is correct for board or we use side books

Posted by Priti Dwivedi 6 years, 4 months ago

CBSE > Class 12 > Chemistry

3 answers

Sahil Kumar 6 years, 4 months ago

Take concept from ncert books and show your potential from side books like HC Verma, Oswal books etc.. For better performance in physics use side books... Solve KC Sinha's for mathematics

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Kiran??? Gautam 6 years, 4 months ago

Its enough

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Řøhăň Řąjpůť ✌️✊ 6 years, 4 months ago

For chemistry ncert is enough but for physics ncert + refresher...

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Why we use dry ether in wurtz reaction not wet ether ?

Posted by Akshita Saini 6 years, 4 months ago

CBSE > Class 12 > Chemistry

1 answers

Yogita Ingle 6 years, 4 months ago

Wurtz reaction is carried out with sodium metal which is highly reactive, hence, we have to select a solvent which will not react with the sodium metal. Thus ether becomes the best choice. Similarly the alkyl halide should also dissolve in the solvent . The sodium halide formed should be insolulbe in the solvent which can be easily removed, and alkane formed should remain in solution,

it requires an aprotic solvent as the medium of the reaction.Dry ether proves to be a very good non-polar, aprotic solvent for this purpose. Hence dry ether is used .

eg. CH₃I ----------> CH₃ - CH₃ (in presence of Sodium and Dry ether)

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Bp of water at 750 mmhg is 99.63°c how much sucrose be added to 500 g of h2o such that it boils at 100 °c

Posted by Muskan Dagar 6 years, 4 months ago

CBSE > Class 12 > Chemistry

1 answers

Řøhăň Řąjpůť ✌️✊ 6 years, 4 months ago

ΔTb= (100 + 273) - (99.63 + 273) = 0.37 K >>w1 = 500 g >>Molar mass of sucrose (C12H22O11), M2= 11 × 12 + 22 × 1 + 11 × 16 = 342 g mol^ - 1 >> Kb= 0.52 K kg mol ^- 1 put all these value in the formula ➡️ΔTb=kb*1000*w2/M2*W1 by solving this u will get ur answer 121.67 g of sucrose

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What happens when sulphur dioxide is passed through an aqueous solution of fee salt

Posted by Aarif Saifi 6 years, 4 months ago

CBSE > Class 12 > Chemistry

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Iupac name of pt(nh3)2cl(no2)

Posted by Pratham Bhalla 6 years, 4 months ago

CBSE > Class 12 > Chemistry

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Why halogens have bigger size than noble gas

Posted by Aditya Bhardwaj 6 years, 4 months ago

CBSE > Class 12 > Chemistry

2 answers

Yogita Ingle 6 years, 4 months ago

Generally atomic size decreases while moving from left to right in the periodic table. But in the case of noble gases, they have comparatively higher atomic size than corresponding halogens because of the reason that vanderwaal’s radii (present in noble gases) is much larger than ionic and covalent radii (present in other elements).

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Shubham Sharma 6 years, 4 months ago

halogens have higher size than noble gases due to effective nuclear charge asociated with the respective atom.

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Cuso4.h2o is blue in color and cuso4 is colorless .why

Posted by Sk Enterprises 6 years, 4 months ago

CBSE > Class 12 > Chemistry