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Why sn2 reactivity increases along primary,secondary and tertiary halide?

Posted by Riya Manna 6 years, 6 months ago

1 answers

Nishu Goyal 6 years, 6 months ago

Because nuleophile attack on opposite side to negative charge and it become difficult due to steric hinderence for nucleophile to attack on a tertiary carbon due to bulky groups

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A solution is prepared by dissolved in3.42 gram sugar in 100 gram of water. What will boiling point and freezing point of this solution. Kf and kb from water is 1.86 k/m and 0.52 respectively.

Posted by Sonu Gurjar 6 years, 6 months ago

CBSE > Class 12 > Chemistry

2 answers

Nishu Goyal 6 years, 6 months ago

Take pure solvent boiling point 373.15 K and its frezzing point 273.15 K . Boiling point will be 374.9284approx Frezzing point 266.7888K approx

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Sajid Ali 6 years, 6 months ago

What is the boiling point of pure solvent?

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All minerals are not ores justify?

Posted by Maddy Madhvan 6 years, 6 months ago

CBSE > Class 12 > Chemistry

2 answers

Nishu Sahu 6 years, 6 months ago

Minerals are naturally occurring chemical substance. Ores are the minerals from which metal is isolated. All ores are mineral but all minerals are not ore such as bauxite is a mineral and a ore of aluminum while clay is only a minerals of aluminum.

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Aadesh Yadav 6 years, 6 months ago

What is a chyistry

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Explain balz-schiemann reaxn..m asking this ques again..

Posted by Srishti Choudhary ✍⏳ 6 years, 6 months ago

CBSE > Class 12 > Chemistry

8 answers

Srishti Choudhary ✍⏳ 6 years, 6 months ago

Ohkk..??...??

1Thank You

Ďãřşháñăã Yadav ? ? ? ✊ 6 years, 6 months ago

arrey mai smjh gyi... ? ? Haan dekh liya tha... ? ?

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Srishti Choudhary ✍⏳ 6 years, 6 months ago

Kya????

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Ďãřşháñăã Yadav ? ? ? ✊ 6 years, 6 months ago

hein .. ??!!

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Srishti Choudhary ✍⏳ 6 years, 6 months ago

Mrng m bhi tumhari kuchh baate pdhi maine....bt uske baad sb gayab...

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Srishti Choudhary ✍⏳ 6 years, 6 months ago

Darshu vo kl maine reply kiya tha smjh aaya ya nhi...m voh dekh nhi paii..

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Srishti Choudhary ✍⏳ 6 years, 6 months ago

Dhanyavaad darshu....

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Ďãřşháñăã Yadav ? ? ? ✊ 6 years, 6 months ago

Benzene diazonium chloride on treating with fluoroboric acid followed by heating gives flurobenzene C6H5N=NCl + HBF4 ➡️ C6H5N2BF4 ➡️ C6H5F + N2+ BF3. Benzene diazonium chloride on treating with HBF4 followed by heating with aq. sodium nitrite solution presence of copper, nitrobenzene is formed. this is all about Balz-Schiemann Reaction.

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What is solvate isomerism?

Posted by Jaya Mehta 6 years, 6 months ago

CBSE > Class 12 > Chemistry

1 answers

Sia ? 6 years, 6 months ago

Solvate or hydrate isomerism are the isomers which have the same composition but the solvate isomers differ by whether or not a solvent molecule is directly bonded to the metal ion or is merely present on free solvent molecules in the crystal.

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When Cl2 reacts with excess of F2,ClF3 is formed and not FCl3??

Posted by Vishakha Dixit 6 years, 6 months ago

CBSE > Class 12 > Chemistry

1 answers

Rishabh Rathi 6 years, 6 months ago

FCl3 does not exist because F is from 2nd period, it can't expand its octet neither it has d orbital.

2Thank You

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Best side book for chemistry

Posted by Asha Mehta 6 years, 6 months ago

CBSE > Class 12 > Chemistry

3 answers

Priya Dharshini 6 years, 6 months ago

For boards use all in one arihant,xamidea. And for jee u can refer o.p tandon..

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Anjali Goyat 6 years, 6 months ago

Grb

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Akash Choudhary Dav Gandhinagar 6 years, 6 months ago

Ncert kafi h Mane to nhi liye agar lena h to pradeep le lo

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Which guide should i use

Posted by Smit Bhandari 6 years, 6 months ago

CBSE > Class 12 > Chemistry

3 answers

K@Łp@N@ $Øđh!?? 6 years, 5 months ago

Ncert is enough

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Akash Choudhary Dav Gandhinagar 6 years, 6 months ago

Ncert only

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Rishabh Rathi 6 years, 6 months ago

Modern abc, Ncert, All in one should be enough

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Elementary step in reaction?????

Posted by Aaaaaaaa Bbbbbbbbb 6 years, 6 months ago

CBSE > Class 12 > Chemistry

2 answers

Yash Rajpoot 6 years, 6 months ago

Each step of a complex reaction is known as elementary Step in reaction.

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Rishabh Rathi 6 years, 6 months ago

Elementary reaction are reaction which occur in one step and complex reactions are composed of elementary reactions. Basically it means every step in a complex reactions is elementary so rules of elementary reactions work on steps but not on the reaction as whole.

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What is conductivity??

Posted by Aaaaaaaa Bbbbbbbbb 6 years, 6 months ago

CBSE > Class 12 > Chemistry

1 answers

Ďãřşháñăã Yadav ? ? ? ✊ 6 years, 6 months ago

inverse of resistivity.. is known as conductivity

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Why H2o exist in liquid where as other like (H2s )ard gases ? Comment

Posted by Surinder Singh 6 years, 6 months ago

CBSE > Class 12 > Chemistry

3 answers

Nishu Goyal 6 years, 6 months ago

Because H2 bond is week covalent bond so cant hold molecules tightly to form solid or liquid but H2O show ionic bond and also hydrogen bonding which are enough strong to hold molecule and form liquid

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Rishabh Rathi 6 years, 6 months ago

Hydrogen bonding

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Akhileshwar Singh 6 years, 6 months ago

Because of elctronegativity

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What is antimicrobials

Posted by Krushika Solanki 6 years, 6 months ago

CBSE > Class 12 > Chemistry

1 answers

Vishakha Dixit 6 years, 6 months ago

Antimicrobial is an agent that kills microorganisms or stops their growth.

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Conductivity of CH3COOH decreases on dilution???

Posted by Vishakha Dixit 6 years, 6 months ago

CBSE > Class 12 > Chemistry

1 answers

Rishabh Rathi 6 years, 6 months ago

Concentration of ions decrease, thus it will result in decrease in conductivity of electricity.

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Why blocks of magnasium are strapped to the steel hulls of ocean going ships?

Posted by Prajwal Baranwal 6 years, 6 months ago

CBSE > Class 12 > Chemistry

0 answers

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The treatment of alkyl chloride with aqueous koh leads to the formation of alcohol but in the presence of alcoholic kohl alkenes are major products. Explain

Posted by Harshika Sahu 6 years, 6 months ago

CBSE > Class 12 > Chemistry

2 answers

Rohit Kumar 6 years, 6 months ago

Hello Ankit

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Rishabh Rathi 6 years, 6 months ago

Its because alc. KOH will give elimination while aq. KOH will give substitution

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What is the best topic for project chemistry

Posted by Mantasha M 6 years, 6 months ago

CBSE > Class 12 > Chemistry

2 answers

Naveen Kumar Sharma 6 years, 6 months ago

Invisible ink

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Naveen Kumar Sharma 6 years, 6 months ago

amoun caesin in milk

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What is faraday law

Posted by Adityakumar Bharti 6 years, 6 months ago

CBSE > Class 12 > Chemistry

1 answers

Ďãřşháñăã Yadav ? ? ? ✊ 6 years, 6 months ago

There are 2 law of faraday 1st law :-- whenever magnetic flux linked with the closed loop or circuit changes an emf induces in the loop or circuit which lasts so long as change in flux continues. 2nd law:--- the induced emf in a closed loop or circuit is directly proportional to the rate of change of magnetic flux linked with the closed loop or circuit.

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Why Hg2+ salts are colourless

Posted by Tannu Rohilla 6 years, 6 months ago

CBSE > Class 12 > Chemistry

1 answers

Sia ? 6 years, 6 months ago

Hg atomic number is 80 .in the oxidation state of +2 it loses two electrons then it has comlpletely filled d-orbitals and also in the Hg2^2+ loses 1 electron .in this salts d-d transition is not possible so they are colourless.

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What is a cell ? how many types of cells are there ?

Posted by Seetala Devi 6 years, 6 months ago

CBSE > Class 12 > Chemistry

2 answers

Sia ? 6 years, 6 months ago

Cell is the smallest structural and functional unit of an organism, which is typically microscopic and consists of cytoplasm and a nucleus enclosed in a membrane.
200 different types of cells are there.

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Nishu Goyal 6 years, 6 months ago

Cell is a device used to form electric or chemical energy . It is of two types electrochemical cell and electrolytic cell.

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ANSWER

Topics. For practical

Posted by Ankit Kumar 6 years, 6 months ago

CBSE > Class 12 > Chemistry

1 answers

Pranjal Patel 6 years, 6 months ago

Chemistry in everyday life is the best topic

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Topics for practical

Posted by Ankit Kumar 2 years ago

CBSE > Class 12 > Chemistry

1 answers

Sia ? 6 years, 6 months ago

Micro-chemical methods are available for several of the practical experiments. Wherever possible, such techniques should be used.

Surface Chemistry
1. Preparation of one lyophilic and one lyophobic sol Lyophilic sol - starch, egg albumin and gum Lyophobic sol - aluminium hydroxide, ferric hydroxide, arsenous sulphide.
2. Dialysis of sol-prepared in (a) above.
3. Study of the role of emulsifying agents in stabilizing the emulsion of different oils.
Chemical Kinetics
1. Effect of concentration and temperature on the rate of reaction between Sodium Thiosulphate and Hydrochloric acid.
2. Study of reaction rates of any one of the following:
  1. Reaction of Iodide ion with Hydrogen Peroxide at room temperature using different concentration of Iodide ions.
  2. Reaction between Potassium Iodate, (KIO₃) and Sodium Sulphite: (Na₂SO₃) using starch solution as indicator (clock reaction).

Thermochemistry
Any one of the following experiments
1. Enthalpy of dissolution of Copper Sulphate or Potassium Nitrate.
2. Enthalpy of neutralization of strong acid (HCI) and strong base (NaOH).
3. Determination of enthalpy change during interaction (Hydrogen bond formation) between Acetone and Chloroform.
D. Electrochemistry
Variation of cell potential in Zn/Zn²⁺|| Cu²⁺/Cu with change in concentration of electrolytes (CuSO₄ or ZnSO₄) at room temperature.
Chromatography
1. Separation of pigments from extracts of leaves and flowers by paper chromatography and determination of Rfvalues.
2. Separation of constituents present in an inorganic mixture containing two cations only (constituents having large difference in Rf values to be provided).
Preparation of Inorganic Compounds
1. Preparation of double salt of Ferrous Ammonium Sulphate or Potash Alum.
2. Preparation of Potassium Ferric Oxalate.
Preparation of Organic Compounds Preparation of any one of the following compounds
1. Acetanilide
2. Di -benzal Acetone
3. p-Nitroacetanilide
4. Aniline yellow or 2 - Naphthol Aniline dye.
Tests for the functional groups present in organic compounds:
Unsaturation, alcoholic, phenolic, aldehydic, ketonic, carboxylic and amino (Primary) groups.
Characteristic tests of carbohydrates, fats and proteins in pure samples and their detection in given food stuffs.

Determination of concentration/ molarity of KMnO4 solution by titrating it against a standard solution of:
1. Oxalic acid,
2. Ferrous Ammonium Sulphate (Students will be required to prepare standard solutions by weighing themselves).
Qualitative analysis
Determination of one cation and one anion in a given salt.
Cation - Pb²⁺, Cu²⁺, Al³⁺, Fe³⁺, Mn²⁺, Zn²⁺, Cu²⁺, Co²⁺, Ni²⁺, Ca²⁺, Sr²⁺, Ba²⁺ , Mg²⁺,[NH4]⁺
Anions – [CO₃]^2- , S^2- , [SO₃]^2- , [SO₄]^2- , [NO₂]^- , Cl^- ,Br^- , I^- , [PO₄]^3- , [C₂O₄]^2- , CH₃COO^- (Note: Insoluble salts excluded)

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Explain a-Finkelstcin reaction

Posted by Naveen Janghela 6 years, 6 months ago

CBSE > Class 12 > Chemistry

2 answers

S.....Sharma☺??? .. 6 years, 6 months ago

The exchange of halogen in which the halogen (x=Br cl )is replaced by lodine when treated with Nal

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Abhishek Pal 6 years, 6 months ago

When an alkyl halide change in iodo alkyl in the prsense dry acetate and naI

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Is organometallic compounds in our syllabus?

Posted by Kriti Bhatia 6 years, 6 months ago

CBSE > Class 12 > Chemistry

1 answers

Rishabh Rathi 6 years, 6 months ago

No we don't study them in detail.

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What is ideal and non-ideal solutions

Posted by Sunita Sahu 6 years, 6 months ago

CBSE > Class 12 > Chemistry

2 answers

Veena Singh☺️? 6 years, 6 months ago

The solutions which obey Raoult's law are called ideal solutions and which don't obey Raoult's law are called non ideal solutions .

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Manesh Tandel 6 years, 6 months ago

Ideal solution are those which obey Raoult's law and non ideal do not obey Raoult's law.

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Half yearly syllabus of chemistry

Posted by Anjali Singh 6 years, 6 months ago

CBSE > Class 12 > Chemistry

3 answers

Priya Dharshini 6 years, 6 months ago

It depends upon ur school....

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Srishti Choudhary ✍⏳ 6 years, 6 months ago

Its depends on ur school teachers...how much did they do??

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Ďãřşháñăã Yadav ? ? ? ✊ 6 years, 6 months ago

1st book puri agar apke schl ne pehle 1st book start ker di... ya toh 2nd book puri agar apke schl ne 2nd book pehle ker di.

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Formula of amide and amine or what is difference between them

Posted by S.....Sharma☺??? .. 6 years, 6 months ago

CBSE > Class 12 > Chemistry

2 answers

Nasima Khan 6 years, 6 months ago

The main difference between amine and amide is the prescence of a carbonyl group in their structure amine have no carbonyl group attached to nitrogen atom whereas amide have a carbonyl group attached to nitrogen atom.

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Md Shammy 6 years, 6 months ago

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What is the Value of log4

Posted by Sneha Kumari 6 years, 6 months ago

CBSE > Class 12 > Chemistry