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Not at all .you can prepare yourself. It will caught you in web of confusion that whether to pay attention at school or at tution as syllabus will be carried out differently. But if still you opt to have it ,then please have clear mind and choose your priority .Bcoz it will decide your future. All the best...

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H!Mαη$Hμ Ұαδαυ ✔️ 7 years, 6 months ago

If you can understand topics easily or your school teachers can help you to understand topics then you must not take tution but if your school teachers are not good then you must prefer to take tution....

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Deepanshu Jaiswal 7 years, 6 months ago

Never you have to do own study in class 12 but you take tuition in summer vocation . But vocation is over.

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Mahima Praja Pati 7 years, 6 months ago

No it is not a necessary to take tuition in 12th class. tuition for those student which get the problem in numericals or some topics

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ANSWER

Definition of average rate of reaction

Posted by Abd Fan 7 years, 6 months ago

CBSE > Class 12 > Chemistry

1 answers

Taniya R 7 years, 6 months ago

It's defined as change in concentration of reactant or product divided by the time interval over which change occurs

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ANSWER

Hi frnda explain molecular orbital theory

Posted by Shaista Parveen 7 years, 6 months ago

CBSE > Class 12 > Chemistry

1 answers

Shaista Parveen 7 years, 6 months ago

Explain molecular orbita tgeory

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ANSWER

The IUPAC NAME OF 6-BROMO-2-CHLOROCYCLOHEXENE

Posted by Niraj Pathak 7 years, 6 months ago

CBSE > Class 12 > Chemistry

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What is n type and p type semiconductors????

Posted by Swati Singh 7 years, 6 months ago

CBSE > Class 12 > Chemistry

3 answers

Anju Kashyap 7 years, 6 months ago

N stands for negative type semiconductor and p stand for positive type semi conductor for example. Whengp 15 elements p or As isadded to Si or Ge which are insulator become semiconductor . Since electrons are the charged carrier hence are called n- type semiconductor

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Yogita Ingle 7 years, 6 months ago

n-type semiconductor

When pure Si or Ge which has four valency electrons is doped with controlled amount of pentavalent atoms, like Arsenic, Phosphorus, Antimony or Bismuth, we get a n-type semiconductor
The four valence electron from the impure atom will combine with four electrons of the Si or Ge atom to form 4 covalent bonds
The fifth electron of the impure atom is free to move. Thus, each atom of the impure substance, donates a free electron for conduction. Hence, it is called as donor atom
Giving the free electron for conduction, the impure atom becomes positively charged, giving rise to a hole
Thus in n-type semiconductors, electrons are the majority carriers and holes are minority carriers.

p-type semiconductor

When pure Si or Ge which has four valency electrons is doped with controlled amount of trivalent atoms, like Gallium, Indium, Boron or Aluminium, we get a p-type semiconductor
The three valence electron from the impure atom will combine with three electrons of the Si or Ge atom to form 3 covalent bonds
There will be one unbounded electron in the Ge atom which would try to form a covalent bond with the neighbouring Ge atom
This Ge-Ge covalent bond creates a deficiency of electron in Ge atom. Thus, creating a hole
This hole is compensated by the breakage of Ge-Ge covalent bond in the neighbourhood. Hence, electron moves towards the hole, resulting in hole formation at some other place
The trivalent atoms are called acceptor atoms and conduction of electricity is due to the motion of holes
Thus in p-type semiconductors, holes are the majority carriers and electrons are minority carriers.

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Swati Singh 7 years, 6 months ago

Please koi explain kar de.... Books m kai baar padh chuki kuch smhj nhi aa rha

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ANSWER

Packing efficiency

Posted by Patel Abdulla Ahmad 7 years, 6 months ago

CBSE > Class 12 > Chemistry

1 answers

Shivanshi Singh 7 years, 6 months ago

The % of space occupied by particle in the given crystal lattice is said to be paking efficiency.

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ANSWER

Platinum forms fcc and density given 21.45 at 20temp. What is the metallic radius of pt?

Posted by Roshani Rajbhar 7 years, 6 months ago

CBSE > Class 12 > Chemistry

0 answers

ANSWER

How to calculate oxidation state in complexes

Posted by Samira Roy 7 years, 6 months ago

CBSE > Class 12 > Chemistry

0 answers

ANSWER

Define semiconductor and its two main types and explain mechanism

Posted by Anurag Singh 7 years, 6 months ago

CBSE > Class 12 > Chemistry

0 answers

ANSWER

define wurtz reaction?

Posted by Amreen Bano 7 years, 6 months ago

CBSE > Class 12 > Chemistry

1 answers

Swati Singh 7 years, 6 months ago

Two molecules of alkyl halide react with sodium in dry ether medium it is form higher alkane this reaction is known as wurtz reaction

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ANSWER

Name an important alloy which contains some of the lanthanoid metal

Posted by Swati Singh 7 years, 6 months ago

CBSE > Class 12 > Chemistry

2 answers

Swati Singh 7 years, 6 months ago

Answer please

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Swati Singh 7 years, 6 months ago

This question was asked in board examination

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ANSWER

How to read comparmental exam

Posted by Harshit Verma 7 years, 6 months ago

CBSE > Class 12 > Chemistry

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ANSWER

Why terchary alkylhalaide show SN1 reaction easily comparison to primary alkylhalaide

Posted by Manish Gautam 7 years, 6 months ago

CBSE > Class 12 > Chemistry

1 answers

Athmika Prajesh 7 years, 6 months ago

Tertiary alcohols have 3 alkyl groups attached to X containing carbon atom. These R grops are electron releasing groups and there by releases the electrons to the X containing Carbon and thus making the carbo cation stable. In SN1 reaction the alkyl halide forms carbocation and halide ion. The carbocation in tertiary is more stable so it is easy for nucleophile to attack it. Thus it follows SN1

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Calculate the molarity and normality of a solution containing 0.5 g of NaOH dissolved in 500 ml solution

Posted by Monal Singh 7 years, 6 months ago

CBSE > Class 12 > Chemistry