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Which separation technique is used to separate substance from any type of mixture?

Posted by Vipul Pandya 6 years, 3 months ago

CBSE > Class 12 > Chemistry

0 answers

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Why SO2 is reducing agent and TeO2 is oxidising agent?

Posted by Raman Brar 6 years, 3 months ago

CBSE > Class 12 > Chemistry

2 answers

Ron Vineetahuja 6 years, 3 months ago

Because due to inert pair effect

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Vishal Kumar 6 years, 3 months ago

SO2 is reducing agent because sulphur has d orbital so it can easily expand its oxidation state +4 to +6 and thus behave as reducing agent. But in case of TeO2, tellurium is a heavier element, it can not exhibit higher oxidation state +6 due to inert pair effect so, it only undergoes reduction ( +4 to +2 ) thus it act as an oxidising agent.

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Si3 O9(having three tetrahedral) is represented as:

Posted by Pallavi Joshi 6 years, 3 months ago

CBSE > Class 12 > Chemistry

2 answers

Vishal Kumar 6 years, 3 months ago

( Si3O9 )^6 - can represented as Three membered cyclic silicate

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Utkarsh Pandey 6 years, 3 months ago

I didn't get question....pls ask clear

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Can a reaction have zero activation energy??

Posted by Shivam Bajpai 6 years, 3 months ago

CBSE > Class 12 > Chemistry

1 answers

Div¥@N$Hi P@M@® 6 years, 3 months ago

Nooo

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investigatory project ke baare m

Posted by Yuvraj Singh 6 years, 3 months ago

CBSE > Class 12 > Chemistry

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A solution contain in 1.9 g per 100 ml of kcl is isotonic with a solution contaning 3 g per 100 mlof urea calculate degree of dissociation of kcl solution assume both the solution have same temprature ?

Posted by Vedika Saxena 6 years, 3 months ago

CBSE > Class 12 > Chemistry

1 answers

Sia ? 6 years, 3 months ago

According to the question, a solution containing 1.9 g per 100 mL of KCl (M = 74.5 g mol^–1) is isotonic with a solution containing 3 g per 100 mL of urea (M = 60 g mol^–1 ).
As solution is isotonic,
{tex}\pi_1{/tex} (urea) = {tex}\pi _2 {/tex} (KCI)
{tex}\Rightarrow {/tex}C₁RT = iC₂RT
{tex}\Rightarrow {/tex}{tex}\frac { n _ { 1 } } { V 1 } = \mathrm { i } \frac { n _ { 2 } } { V 2 }{/tex} ({tex}\because {/tex}V₁ = V₂)
{tex}\Rightarrow {/tex}{tex}\frac { 3 } { 60 } = \mathrm { i } \times \frac { 1.9 } { 74.5 }{/tex}
{tex}\Rightarrow {/tex}i = 1.96
We know that, {tex}\alpha = \frac { i - 1 } { n - 1 }{/tex}
{tex}= \frac { 1.96 - 1 } { 2 - 1 } \\= 0.96{/tex}
= 96%

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What is cataiens

Posted by Himanshu Upadhyay 6 years, 3 months ago

CBSE > Class 12 > Chemistry

1 answers

Vishal Kumar 6 years, 3 months ago

Cation is a positively charged atom.

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Recemization

Posted by Gajendra Suman 6 years, 3 months ago

CBSE > Class 12 > Chemistry

3 answers

Avinash Yadav 6 years, 3 months ago

The process of converting an enantiomer into racemic mixture,is known as racemisation.

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Ron Vineetahuja 6 years, 3 months ago

Racemisation is a process of forming a mixture of d and l enantiomorphs

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Sia ? 6 years, 3 months ago

Racemization occurs when one pure form of an enantiomer is converted into equal proportion of both enantiomers, forming a racemate.

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Difference between conductivity and molar conductivity

Posted by Rutuja Murhe 4 years, 6 months ago

CBSE > Class 12 > Chemistry

1 answers

Sia ? 4 years, 6 months ago

Conductivity is the conductance per unit volume of the solution; it may also be considered as the concentration of ions per unit volume of solution. Molar Conductivity is the conductance of the entire solution having 1 mole of electrolyte dissolved in it.

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Benzyl chloride is highly reactive towards the sn1reaction

Posted by Ekta Rai 6 years, 3 months ago

CBSE > Class 12 > Chemistry

3 answers

Kishan Kumar 6 years, 3 months ago

Because after removal of chlorine the carbocation formed will be more stable by resonance thus the reaction which includes formation of most stable carbocation always are higly reactive towards SN1.

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Div¥@N$Hi P@M@® 6 years, 3 months ago

Noo

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Gamer Gk 6 years, 3 months ago

Are u from chinmaya??

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Chemical kinetics of class 12 has a error. The solutions of the ncert question are written in coding form....... (Like question 28,29,30) .... Numericals solutions are difficult to understand

Posted by Gamer Gk 6 years, 3 months ago

CBSE > Class 12 > Chemistry

0 answers

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Why OH group attacks from backward side in SN2 reaction?

Posted by Raman Brar 6 years, 3 months ago

CBSE > Class 12 > Chemistry

1 answers

Div¥@N$Hi P@M@® 6 years, 3 months ago

Beacuse Sn2 reaction involved front back mechanism in which group is attacks from back side and other group leaving from front side.

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Fractional distillation

Posted by Faiz Malik 6 years, 3 months ago

CBSE > Class 12 > Chemistry

1 answers

Khuskaran Sidhu 6 years, 3 months ago

If boiling points of two components in a mixture are different and we want to separate them,then frac..........

1Thank You

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Kya general principles of isolation chapter syllabus se hat gya h????

Posted by Anshika Tiwari 6 years, 3 months ago

CBSE > Class 12 > Chemistry

7 answers

Avinash Yadav 6 years, 3 months ago

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Deeya Singh 6 years, 3 months ago

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꧁≪Mämƭå ℭℏ۝ᑌĎℎàℜÿ? 6 years, 3 months ago

No.. it's still there..?

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Gajendra Suman 6 years, 3 months ago

0Thank You

Ron Vineetahuja 6 years, 3 months ago

No yeh syllabus mein hai

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Khuskaran Sidhu 6 years, 3 months ago

No,it is in syllabus

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Sandeep Tyagi Sandeep Tyagi 6 years, 3 months ago

Nahin ye syllabus me hain

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the mole fraction of methanol in its 4.5 molal aqueous solution is

Posted by Deepanshi Tripathi 6 years, 3 months ago

CBSE > Class 12 > Chemistry

1 answers

Sia ? 6 years, 3 months ago

{tex}Mole\;fraction,\;x\;=\frac{\frac wm}{\frac wm+\frac WM}{/tex}
(where, w and m represent the mass and molar mass of solute and W and M represent the mass and molar mass of solvent.)
{tex}\frac1x\;=\frac{\frac wm+\frac WM}{\frac wm}{/tex}
{tex}\frac1x=1+\frac{W\times m}{M\times w}\times\frac{1000}{1000}{/tex}
{tex}\frac1x=1+\frac{1000}{M\times m}{/tex}({tex}\because{/tex}Molality, {tex}m=\frac{w\times1000}{m\times W}{/tex})
{tex}=1+\frac{1000}{18\times4.5}{/tex} ({tex}\because{/tex} Molor mass of H₂O=18gmol^-1)
{tex}=1+\frac{1000}{81}{/tex}
{tex}=\frac{1081}{81}=13.34{/tex}
{tex}x=\frac1{13.34}=0.075{/tex}

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ANSWER

A solution of glycerol C3H8O3 in water was prepared by dissolving some glycerol in 500g of water. The solution has boiling point 100.42 while pure water has boling point 100

Posted by Divyansh Batra 6 years, 3 months ago

CBSE > Class 12 > Chemistry

1 answers

Sia ? 6 years, 3 months ago

Given, Mass of solute (glycerol) (W₂) =?
Molar mass of solute (M₂) = 92 g mol^-1
Mass of solvent (water) (W₁) = 500g
{tex}\Delta{/tex}T_b = 100.42^oC - 100^oC
= 0.42^oC = 0.42 k
K_b = 0.512 k kg mol^-1
{tex}\therefore{/tex} {tex}\Delta{/tex}T_b = K_b {tex} \times \frac{{{W_2}}}{{{M_2}}}{/tex}{tex}\times{/tex} {tex}\frac{100}{W_1}{/tex} {tex}\therefore{/tex} W₂ = {tex}\frac{{{\Delta T_b} \times {M_2}\, \times {W_1}\,}}{{{K_b} \times \,100}}{/tex}
W₂ = {tex}\frac{{0.42 \times 92\, \times 500\,}}{{0.512 \times 1000}}{/tex}
W₂ = 37.73 g
Hence, the mass of glycerol dissolved = 37.73 g.

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The electron affinity of chlorine is higher than fluorine why

Posted by Pragati Gautam 6 years, 3 months ago

CBSE > Class 12 > Chemistry

2 answers

Raman Brar 6 years, 3 months ago

Due to large size of chlorine then fluorine.there is small electron cloud in flourine and replusion is very much.

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Anshika Tiwari 6 years, 3 months ago

Because chlorine have half filled orbital

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Effect of temperature on solubility of solid in liquid and gas in liquid

Posted by Kirti Singh 6 years, 3 months ago

CBSE > Class 12 > Chemistry

4 answers

Avinash Yadav 6 years, 3 months ago

For solubility of solid in liquid_ if the reaction is endothermic then it will increase with increase in temperature but if it is exothermic then it will decrease with increase in temperature. For solubility of gas in liquid _ It decrease with increase in temperature but increase with decrease in temperature, Solubility is inversely proportional to temperature.

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Vikas Semwal 6 years, 3 months ago

Solubility increases with increase in temp for solid in liquid ex sugar and water...... Solubility is inversely proportional for gas and liquid ex aquatic animals felt calm in cold water than in warm water

1Thank You

Isha Raj 6 years, 3 months ago

it is for gas?

1Thank You

Isha Raj 6 years, 3 months ago

solubility is inversely proportional to temperature

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Except fluorine, halogens don't combine with oxygen directly WHY?

Posted by Vaibhav Singh 6 years, 3 months ago

CBSE > Class 12 > Chemistry

1 answers

Vikas Semwal 6 years, 3 months ago

Because F is capable due to smaller size, high electro negativity

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A investigatory project containt

Posted by Mohammad Amannullah 6 years, 3 months ago

CBSE > Class 12 > Chemistry

0 answers

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Calculate the temperature at which average velocity of oxygen gas is 1500m/sec

Posted by Abhaykumar Gautam 6 years, 3 months ago

CBSE > Class 12 > Chemistry

0 answers

ANSWER

Formula of weatstone bridge

Posted by Roma Khatwani 6 years, 3 months ago

CBSE > Class 12 > Chemistry

2 answers

Muskan Jangra 6 years, 3 months ago

P/Q=R/S where R is unknown resistance whose resistance we have to find it

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Rishabh Rathi 6 years, 3 months ago

(R1/R4)=(R2/R3) or R1.R3=R2.R4. Here resistors are named in clockwise manner

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Sandmayer reaction

Posted by Upasana Upa 6 years, 3 months ago

CBSE > Class 12 > Chemistry

2 answers

Sia ? 6 years, 3 months ago

The Sandmeyer reaction is a chemical reaction used to synthesize aryl halides from aryl diazonium salts using copper salts as reagents or catalysts. It is an example of a radical-nucleophilic aromatic substitution.

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Deepika Joshi 6 years, 3 months ago

https://goo.gl/search/Sandmeyer+reaction Sandmeyer reaction,

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Structural formula of 1chloro 4 methylbenzene amd 1 bromo 2 methylbenzene

Posted by Upasana Upa 6 years, 3 months ago

CBSE > Class 12 > Chemistry

0 answers

ANSWER

Write the chemical equation involved in the conversion of ethanol to diethylether

Posted by Lalchhanhimi Zote 6 years, 3 months ago

CBSE > Class 12 > Chemistry

1 answers

Sia ? 6 years, 3 months ago

H₂SO₄, 413 K
{tex}\underset{Ethanol}{2\;CH_3-CH_2-OH}\rightarrow\underset{Ethoxy\;ethane\;(or\;Diethyl\;ether)}{CH_3-CH_2-O-CH_2-CH_3\;+\;H_2O}{/tex}

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Guyz kya mechanism jaruri h ya direct main reaction yaad kar lu plzz tell me mujhe sirf board ka exam dena uske point of view se

Posted by Prashant Singh 6 years, 3 months ago

CBSE > Class 12 > Chemistry

3 answers

Manika Gupta 6 years, 3 months ago

From the point of board mechanism is imp we have 4 mechanism in our course and 1 mechanism each year come in 3 marks...

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Sunmeet Kaur Sachdeva 6 years, 3 months ago

Mechanism is important

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Moni Sheoran@2#3% 6 years, 3 months ago

yes ,mainly mechanism of hydration & dehydration..

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how to find stable oxidation state of the Transition Element with following ground state electronic configuration 3d3

Posted by Vikas Semwal 6 years, 3 months ago

CBSE > Class 12 > Chemistry

0 answers

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Why glucose does not gives 2 4 DNP test

Posted by Keshav Choudhary 6 years, 3 months ago

CBSE > Class 12 > Chemistry

1 answers

Mehak Verma 6 years, 3 months ago

Although, glucose in its open chain structure contains a free aldehydic group yet it does not give 2,4-DNP test, a characteristic reaction of aldehyde,i.e. -CHO group. This is because glucose actually exists in the cyclic hemiacetal form with only a small amount of the open chain form in equilibrium. Since,the concentration of the open chain form is very low and its reaction with 2,4-DNP are reversible, thus its 2,4-DNP adduct is generally not observed.

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What is the oxidation state of flourine in HOF??

Posted by Arahida Hashmi 6 years, 3 months ago

CBSE > Class 12 > Chemistry