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What is wrought iron

Posted by Abhishek Rana 7 years, 4 months ago

1 answers

Nitika Neb 7 years, 4 months ago

Wrought iron is an iron alloy with a very low carbon content in contrast to cast iron. It is a semi-fused mass of iron with fibrous slag inclusions, which gives it a "grain" resembling wood that is visible when it is etched or bent to the point of failure.

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How to find oxidation state

Posted by Vidya Sree 5 years, 11 months ago

CBSE > Class 12 > Chemistry

2 answers

Kt Kt 7 years, 4 months ago

The residual charge left on an atom after removel of all electrons in it

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Adithyan Karthik 7 years, 4 months ago

Please refer +1, 2nd text

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Name is dacron synthesis? Give chemical reaction?

Posted by Vikas Patel 7 years, 4 months ago

CBSE > Class 12 > Chemistry

1 answers

Nitika Neb 7 years, 4 months ago

Polyethylene terephthalate (sometimes written poly(ethylene terephthalate)), commonly abbreviated PET, PETE, or the obsolete PETP or PET-P, is the most common thermoplastic polymer resin of the polyester family and is used in fibres for clothing, containers for liquids and foods, thermoforming for manufacturing, and in combination with glass fibre for engineering resins.

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Limitation of roults law

Posted by Abhay Singh 7 years, 4 months ago

CBSE > Class 12 > Chemistry

1 answers

Akash Yadav 7 years, 4 months ago

Raoult’s law is applicable to solutions containing non-volatile solute only.Raoult’s law is not applicable to solutes which dissociate or associate in the particular solution.

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Tincture of iodine

Posted by Mayank Mittal 7 years, 4 months ago

CBSE > Class 12 > Chemistry

2 answers

Adithyan Karthik 7 years, 4 months ago

2-3% of iodine in alcohol and water medium

4Thank You

Nitika Neb 7 years, 4 months ago

Tincture of iodine, iodine tincture, or weak iodine solution is an antiseptic. It is usually 2–7% elemental iodine, along with potassium iodide or sodium iodide, dissolved in a mixture of ethanol and water. Tincture solutions are characterized by the presence of alcohol

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Calculate the emf of the following cell at 25c Fe/Fe2+(0.001m)||H+(0.01m)|H2(yg)(1bar) E(Fe2+/fe)=-0.44v,E(H+/H2)=0.01|pt(s)

Posted by Vishal Kumar 7 years, 4 months ago

CBSE > Class 12 > Chemistry

0 answers

ANSWER

Chapterwise wieghtage ??

Posted by Himanshu Gupta 5 years, 11 months ago

CBSE > Class 12 > Chemistry

1 answers

Mansi Sharma 7 years, 4 months ago

See the blue print dude!

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ANSWER

Convert methanal to 2 methyl propanol by grignard

Posted by Rasnit Shankar 7 years, 4 months ago

CBSE > Class 12 > Chemistry

1 answers

Shorya Chaudhary 7 years, 4 months ago

By addding phynl in it

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Write the mechanism of conversion of propene into propane-2-ol using sulphuric acid.

Posted by Amisha Vashisth 7 years, 4 months ago

CBSE > Class 12 > Chemistry

0 answers

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Why helium

Posted by Pratap Aditya Majee 7 years, 4 months ago

CBSE > Class 12 > Chemistry

1 answers

Mansi Sharma 7 years, 4 months ago

U should write a complete que`

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How to convert propanal to propene??

Posted by Passngkit Lepcha 7 years, 4 months ago

CBSE > Class 12 > Chemistry

1 answers

Yogita Ingle 7 years, 4 months ago

The conversion of propanal to propane is a reduction reaction. This involves the reduction of an aldehyde into a hydrocarbon. There are two methods namely:

1. Clemmesen reduction:The carbonyl group of aldehyde or ketone is converted into CH₂group by treating with Zinc-Amalgam(Zn-Hg) and concentrated hydrochloric acid.

2. Wolf-Kishner reduction:The carbonyl group is converted by the action of hydrazine(NH₂-NH₂) with KOH or NaOH in high boiling solvent such as ethylene glycol.

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How to ethane to butyne

Posted by Ritesh Pal 7 years, 4 months ago

CBSE > Class 12 > Chemistry

0 answers

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Why do d Block elements form coloured and interstial compound give reasons.

Posted by Resham Bawa 7 years, 4 months ago

CBSE > Class 12 > Chemistry

1 answers

Mansi Sharma 7 years, 4 months ago

Because of the d-d transition .

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Phenoxide ion has more no. Of resonating structure than carboxylate ion?why

Posted by Gulrez Aslam 7 years, 4 months ago

CBSE > Class 12 > Chemistry

1 answers

Aryan Singh 7 years, 4 months ago

Because in carboxalate ion the charge donot enter the benzene ring forming two resonating structures. But in phenoxide ion the charge enters the ring and forms six resonating structures.

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What is blister copper

Posted by Aastha Choudhary 7 years, 4 months ago

CBSE > Class 12 > Chemistry

2 answers

Vineet Kumar Gupta 7 years, 4 months ago

It's in the syllabus of jee advance I guess (not in boards)

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Yogita Ingle 7 years, 4 months ago

The molten mass is then cooled. Then it slowly gives dissolved the SO₂ gas in the form of bubbles. So, the copper thus formed is also known as blister copper.
The solidied copper obtained has blistered appearance due to the evolution of SO₂, so it is called blistered copper.

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ANSWER

What is the solid state

Posted by Harshad Patel 7 years, 4 months ago

CBSE > Class 12 > Chemistry

1 answers

Rajat Dhull 7 years, 4 months ago

State in which there are strongly packed atoms and molecules. High intermolecular forces and less intermolecular space.

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ANSWER

F centred

Posted by Vinay Kumar Nishad 7 years, 4 months ago

CBSE > Class 12 > Chemistry

2 answers

Vineet Kumar Gupta 7 years, 4 months ago

Faber centres or Faber (colour) centres that's what was missing in the previous answer

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Jugraj Grewal 7 years, 4 months ago

The electrons trapped in anion vacancies are referred as F-centres.

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When rna

Posted by Ayush Raj 7 years, 4 months ago

CBSE > Class 12 > Chemistry

1 answers

Aryan Singh 7 years, 4 months ago

Ribonucleic Acid.

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What cause charge on colloidal particles?

Posted by Prakhar Vyas 7 years, 4 months ago

CBSE > Class 12 > Chemistry

1 answers

Yogita Ingle 7 years, 4 months ago

The charge on the colloidal particles is due to adsorption of common ions of the electrolyte on the surface of the colloidal particles.
eg: Fe³⁺ from FeCl₃ on the surface of Fe(OH)₃ particle.

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Why blood has negative charge

Posted by Jit G?P✔ ??? 7 years, 4 months ago

CBSE > Class 12 > Chemistry

3 answers

Garima Bansal 7 years, 4 months ago

I think heparin is ryt ?

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Ananya Pal 7 years, 4 months ago

It's a aspirin not heparin

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Yogita Ingle 7 years, 4 months ago

Blood does not coagulate inside the body due to the presence of heparin inside the body.It is anticoagulant and has highest negative charge density.Heparin is a naturally occurring anticoagulant produced by basophils and mast cells.Heparin acts as an anticoagulant, preventing the formation of clots and extension of existing clots within the blood. While heparin does not break down clots that have already formed , it allows the body's natural clotlysis mechanisms to work normally to break down clots that have formed

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What is gold number,in easy way?

Posted by Rafiya Ansari 7 years, 4 months ago

CBSE > Class 12 > Chemistry

1 answers

Nitika Neb 7 years, 4 months ago

Gold no is defined as the minimum wt of protective colloid in milli grams that must be added to 10 ml of red gold sol so as no coagulation can take place when 1ml of 10% Nacl is added to it quickly

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Why transition elements have high enthalpy of atomization?

Posted by Snita Dutta 7 years, 4 months ago

CBSE > Class 12 > Chemistry

2 answers

O Singh 7 years, 4 months ago

Due to large number of unpaired electrons.

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Yogita Ingle 7 years, 4 months ago

Transition metals have high enthalpy of atomization Enthalpy of atomisation is the amount of heat required to break the metal lattice to get free atoms. As transition metals contain a large number of unpaired electrons, they have strong interatomic attractions (metallic bonds). Hence,they have high enthalpies of atomisation.

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A delta is formed at the meeting point of sea water and river water

Posted by Shorya Chaudhary 7 years, 4 months ago

CBSE > Class 12 > Chemistry

2 answers

Garima Bansal 7 years, 4 months ago

Delta formed becoz see water contain electrolytes in it wheras river water contain colloidal particles in the form of soil clay etc. When they meet coagulation occurs and delta formed.

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Gaurav Seth 7 years, 4 months ago

When a single river drains into a big sea or ocean, travelling via other parts of the country it gets spreaded throughout itself and forms, Delta.

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Write the main reason for the stablity of colloide

Posted by Shorya Chaudhary 7 years, 4 months ago

CBSE > Class 12 > Chemistry

2 answers

Gaurav Seth 7 years, 4 months ago

The colloidal particles carry a particular charge and the dispersion medium carries equal but opposite charge. The stability of the colloid is due to these charges only. Due to the presence of these similar and equal charges, the particles of the colloid sol repel one another and cannot combine together to form larger particles which keeps them dispersed in the medium and the colloidal remains stable. For example, in a ferric hydroxide sol, the colloidal ferric hydroxide particles are positively charged, while the dispersion medium carries an equal and opposite negative charge

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Prakash Jaiswal 7 years, 4 months ago

Me too wana know this questions answer

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ANSWER

What is conformational isomer?

Posted by Nidhi Priya 7 years, 4 months ago

CBSE > Class 12 > Chemistry

1 answers

Yogita Ingle 7 years, 4 months ago

Conformational isomers, or conformers for short, are caused by the rotation around covalent single σ bonds and the three-dimensional (3-D) tetrahedral shape of the sp3-hybridized centers.

Eclipse conformation: Conformation in which hydrogen atoms attached to two carbons areas nearest to each other as possible is known as eclipsed
Staggered conformation: Conformation in which hydrogen atoms attached to two carbons are as far as possible with respect to each other is known as staggered The staggered conformation is thus relatively more stable in comparison to eclipse conformation as there are minimum repulsive forces, minimum energy due to much separation between the electron clouds of C-H bonds.

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From which chapters question come more??

Posted by Mantosh Rai 7 years, 4 months ago

CBSE > Class 12 > Chemistry

3 answers

Mansi Sharma 7 years, 4 months ago

This is not sure ...

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Rajat Dhull 7 years, 4 months ago

P block has the highest weightage

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Nidhi Priya 7 years, 4 months ago

Search on google cbse class 12 weitage of chapters

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Important reactions for Organic chemistry

Posted by Nitish Sharma 7 years, 4 months ago

CBSE > Class 12 > Chemistry

1 answers

Rishabh Sahu 7 years, 4 months ago

All the reactions with specific names are important. For being more specific ,see the previous years papers.

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Why does H3PO2 acts as a monobasic acid?

Posted by Vornica Singh 7 years, 4 months ago

CBSE > Class 12 > Chemistry

1 answers

Akash Yadav 7 years, 4 months ago

After drawing the structure of H3PO2 u can see that there is only one -OH attached to Phosphorus which is responsible for basicity of H3PO2

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What is reimer-tiemann reaction?

Posted by Dhirendra Patil 7 years, 4 months ago

CBSE > Class 12 > Chemistry

1 answers

Vornica Singh 7 years, 4 months ago

Treatment of phenol with choloform in the presence of aqueous alkali at 340k followed by hydrolysis of resulting product gives o-hydroxybenzaldehyde (salicylaldehyde) as a major product.

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Banzen chlorine to phenol

Posted by Nikki Singh 7 years, 4 months ago

CBSE > Class 12 > Chemistry