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Which of the following is nylon6,6

Posted by Tanvi Garg 6 years, 1 month ago

CBSE > Class 12 > Chemistry

2 answers

Divya Shrivastav 6 years, 1 month ago

buna s

Aditya Chauhan 6 years, 1 month ago

Where are the options

ANSWER

Arrange following complexes in increasing order if conducting nature of their solution CO(NH3)Cl3 , Co(NH3)4Cl2)Cl , Co(NH3)6Cl , Cr(NH3)5Cl )Cl2

Posted by Amit Ahlawat 6 years, 1 month ago

CBSE > Class 12 > Chemistry

0 answers

ANSWER

Chromyl chloride test is used for what purpose.

Posted by Tamanna Sharma 6 years, 1 month ago

CBSE > Class 12 > Chemistry

1 answers

Aditya Chauhan 6 years, 1 month ago

It is often used as an oxidizing agent. The chromyl chloride can be used for the oxidation of toluene to Benzaldehyde.

ANSWER

For transition elements- valence electrons are present in the s-orbital of outermost shell as well as d-orbitals of penultimate shell.what is meant by this penultimate shell?

Posted by Tamanna Sharma 6 years, 1 month ago

CBSE > Class 12 > Chemistry

5 answers

Tamanna Sharma 6 years, 1 month ago

No mahi, its antepenultimate shell you are right ( i_e)

Mahi D 6 years, 1 month ago

Then does anti-penultimate means n-2?

Vijay Singh 6 years, 1 month ago

n-1 shell

Tamanna Sharma 6 years, 1 month ago

Thanks,?? as my teacher is not able to answer this question yet I asked this question 4 times to her

Aditya Chauhan 6 years, 1 month ago

The shell which is before the valence shell is called penultimate shell. If 'n' is the valence shell then (n-1) is the penultimate shell. Transition elements contain unpaired electrons in penultimate

ANSWER

If both anode and cathode dip in the same electrolyte solution then in this case we do not require a salt bridge.why?and how potential difference generate here as the electrolyte is same(ions have same SRP value)? ((NCERT page 67 article3.2 4 paragraph))

Posted by Tamanna Sharma 6 years, 1 month ago

CBSE > Class 12 > Chemistry

5 answers

Tamanna Sharma 6 years, 1 month ago

How you can say that ellectrical neutrality how we overcome the junction potential here

Mahi D 6 years, 1 month ago

Electrical neutrality is already maintained if u dip both electrodes in same electrolyte. Salt bridge is actually considered inert so as such there is no effect on neutrality of the soln. when both are in same electrolyte.

Tamanna Sharma 6 years, 1 month ago

I mean 'how to maintain eletrical neutrality 'here as it is one of the important function of salt bridge

Mahi D 6 years, 1 month ago

I couldn't understand ur second doubt in ur question

Mahi D 6 years, 1 month ago

Salt bridge is obviously not needed when anode and cathode are dipped in same electrolytic soln. U know it performs the function of transfer of ions so that reduction and oxidation takes place but when both are dipped in same soln. then the ions from the soln. are easily transferred to electrodes so in this case no salt bridge is needed .

ANSWER

Why this reaction CCl3-CH=CH2 + HCl ~ CCI3-CH2-CH2Cl proceed as antimarkonikov rule as there is no peroxide there?

Posted by Tamanna Sharma 6 years, 1 month ago

CBSE > Class 12 > Chemistry

4 answers

Tamanna Sharma 6 years, 1 month ago

Why this secondary carbocation is unstable,explain. is it due to the chlorine

Mahi D 6 years, 1 month ago

Had the mechanism been markovnikov then a secondary carbocation would have developed on CH but here due to more electon withdrawing effect of three cl atoms the charge has become more +ve ... So to reduce this the carbocation will be developed on CH2 even in absence of peroxide.

Tamanna Sharma 6 years, 1 month ago

But all chlorines are not attached to CH2

Pritish Farswan 6 years, 1 month ago

Due to repulsion of three chlorine atoms Cl is attached to CH2 ( may be)

ANSWER

How amalgam is prepared?

Posted by Tamanna Sharma 6 years, 1 month ago

CBSE > Class 12 > Chemistry

2 answers

Aditya Chauhan 6 years, 1 month ago

Please come on the whatsapp

Aditya Chauhan 6 years, 1 month ago

Dental amalgam is produced by mixing liquid mercury with an alloy made of silver, tin, and copper solid particles. Small quantities of zinc, mercury and other metals may be present in some alloys. This combination of solid particles is known as amalgam alloy.

ANSWER

Write the mechanism of preparation of diethyl ether from ethanol

Posted by Apoorva Rao 6 years, 1 month ago

CBSE > Class 12 > Chemistry

0 answers

ANSWER

Hi do we have methods of preparation of halo alkanes and halo arenes

Posted by U Know Me 6 years, 1 month ago

CBSE > Class 12 > Chemistry

2 answers

Aditya Chauhan 6 years, 1 month ago

Yes we have

Tamanna Sharma 6 years, 1 month ago

Yes

ANSWER

What is tincureof iodine?

Posted by Harshit Sharma 6 years, 1 month ago

CBSE > Class 12 > Chemistry

2 answers

Jyoti Verma 6 years, 1 month ago

2 to 3 percent alchohol in water is tincture of iodine

Sourabh Kumar 6 years, 1 month 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.

ANSWER

Chemistry in everyday life

Posted by Sargam Bansal 6 years, 1 month ago

CBSE > Class 12 > Chemistry

0 answers

ANSWER

Limitations of ohm law.?

Posted by Râhūl ;-),?? 6 years, 1 month ago

CBSE > Class 12 > Chemistry

1 answers

Aditya Chauhan 6 years, 1 month ago

Its simple dude ....... This law cannot be applied to unilateral networks. A unilateral network has unilateral elements like diode, transistors, etc., which do not have same voltage current relation for both directions of current.

ANSWER

When NH3 & H2S passed through water then, H2S form bubbles Why ?

Posted by Vaibhav Singh 6 years, 1 month ago

CBSE > Class 12 > Chemistry

1 answers

Aditya Chauhan 6 years, 1 month ago

I think H2s forms blister rather than bubbles and i read that ........... . Blisters form as a result of atomic hydrogen diffusing through metal and accumulating in voids. Being highly reactive, hydrogen atoms combine with each other inside of voids and form hydrogen gas (H2). The buildup of hydrogen gas then increases the pressure beneath the surface of the metal to form blisters.

ANSWER

What is allylic substitution

Posted by Herdev Saini 6 years, 1 month ago

CBSE > Class 12 > Chemistry

1 answers

Aditya Chauhan 6 years, 1 month ago

An allylic substitution is a substitution reaction in which a ligand on an allylic carbon in an organic compound is replaced by another ligand.

ANSWER

Can we separate water completely from HNO3 solution by vapourisation

Posted by Tamanna Sharma 6 years, 1 month ago

CBSE > Class 12 > Chemistry

1 answers

Aditya Chauhan 6 years, 1 month ago

No

ANSWER

A and B liquids on mixing produce a warm solution .which type of deviation from raoult's law is there?

Posted by Tamanna Sharma 6 years, 1 month ago

CBSE > Class 12 > Chemistry

2 answers

Tamanna Sharma 6 years, 1 month ago

Thanks

Aditya Chauhan 6 years, 1 month ago

As the heat is evolved, the enthalpy change is negative. It must be exothermic and also shows negative deviation from raoult's law. Reason for negative deviation: The intermolecular forces between A-A and B-B are weaker than those between A-B. So, when u mix these kind of solutions, heat will be released and also it leads to decrease in vapour pressure. Sorry if any problem in my language

ANSWER

Why does an azeotropic mixture distills without any change in composition??

Posted by Tamanna Sharma 6 years, 1 month ago

CBSE > Class 12 > Chemistry

1 answers

Aditya Chauhan 6 years, 1 month ago

An azeotrope is a mixture of liquids that boils at a constant temperature, at a given pressure, without change of composition. ... When the azeotropic liquid is boiled, it retains the same composition

ANSWER

Solutins of ncert

Posted by Muskan Kumari 6 years, 1 month ago

CBSE > Class 12 > Chemistry

1 answers

Aditya Chauhan 6 years, 1 month ago

You can download it from net or buy Ncert solution...

ANSWER

How we can verify that electrolytic cell drives a non spontaneous redox reaction ?

Posted by Tamanna Sharma 6 years, 1 month ago

CBSE > Class 12 > Chemistry

4 answers

Yogita Ingle 6 years, 1 month ago

Sorry for wrong posting

Yogita Ingle 6 years, 1 month ago

Kreb’s cycle takes place in the mitochondrial matrix.
Several intermediate compounds are formed, which contain three carboxylic groups and therefore the process is called as tricarboxylic acid cycle (TCA).
First, the condensation of acetyl group with oxaloacetic acid (OAA) and water takes place to yield citric acid, catalysed by the enzyme citrate synthase and a molecule of CoA is released.
Citrate is then isomerised to isocitrate, which is followed by two successive steps of decarboxylation, leading to the formation of α-ketoglutaric acid and then succinyl-CoA.
Succinyl-CoA is oxidised to OAA allowing the cycle to continue and during the conversion of succinyl-CoA to succinic acid a molecule of GTP is synthesised.
In a coupled reaction, GTP is converted to GDP with the simultaneous synthesis of ATP from ADP.

Pyruvic acid + 4 NAD⁺ + FAD⁺ + 2H₂O + ADP + Pi à 3CO₂+ 4NADH + 4H⁺+ FADH₂+ ATP

During the process, 8NADH₂, 2FADH₂, 2 GTPs are formed.

Aditya Chauhan 6 years, 1 month ago

Since there is decomposition we need to provide energy hence it is non spontaneous ..........but you didnt salute me ..........as i gave the answer of how water is used as fire extinguisher...

Aditya Chauhan 6 years, 1 month ago

An electrolytic cell is an electrochemical cell that drives a non-spontaneous redox reaction through the application of electrical energy. They are often used to decompose chemical compounds, in a process called electrolysis—the Greek word lysis means to break up.

ANSWER

Difference between drug and medicine

Posted by Pankaj Sahani 6 years, 1 month ago

CBSE > Class 12 > Chemistry

2 answers

Tamanna Sharma 6 years, 1 month ago

It's incomplete answer because drugs have 2 categories 1. narcotic 2. non narcotic

Yogita Ingle 6 years, 1 month ago

All medicines are drugs but all drugs are not medicines. Medicines generally are not addictive in nature, unlike drugs. Medicines are made for the treatment of a particular disease, while drug is often considered as narcotic, a stimulant or hallucinogen. Medicines never cause stupefaction while drugs do.

ANSWER

Importnt topics for numerical

Posted by Vishavpreet Singh 6 years, 1 month ago

CBSE > Class 12 > Chemistry

2 answers

Vishavpreet Singh 6 years, 1 month ago

Thnks

Aditya Chauhan 6 years, 1 month ago

All ncert Numericals And rest The important topics of class 12 chemistry board exam are: 1)Solid State - Packing 2)Solutions- All the Colligative Props 3)Electrochem- Nernst eqn and all the formulae 4)Chem Kinetics- Corresponding equations of all the orders and Activation Energy 5)Surface Chem- All definitions; and Colloids 6)Metallurgy- Remember all the ores of all metals and extraction processes 7)P block- trends in each group, uses of all compounds and reactions 8) D and F block- same as above 9)Coordination Chemistry- All definitions; CFT; Isomerism 10) RX ArX - All mechanisms (SN1 ,2, SE, NA) 11) ROH,ArOH,ROR- Rxns( Kolbe, Reimer-Teimann , Williamson synth) and mechanisms 12)RCHO, RCOR,RCOOH- All types of synthesis rxns and rxn of NH3 derivatives with carbonyl group 13)Amines-Hoffmann Bromamide, Gabriel Phthalamide, Carbylamine and Diazonium grp 14) Biomolecules- All rxns of Glucose, Hydrolysis products of polysaccharides and all protein structures 15)Polymers- Uses and monomers of all polymers, reactions 16)CIEL- Definitions of all medicinal compounds and atleast 2 eg of each; Soaps Once you have done the topic please do see previous year papers of CBSE so that you get to know exactly what type of questions and what percentage of marks its constitute. All the best for our Exams……

ANSWER

Henry law define

Posted by Shri Krishna 6 years, 1 month ago

CBSE > Class 12 > Chemistry

1 answers

Aditya Chauhan 6 years, 1 month ago

In physical chemistry, Henry's law is a gas law that states that the amount of dissolved gas in a liquid is proportional to its partial pressure above the liquid. The proportionality factor is called Henry's law constant.

ANSWER

Why it is essential to wash the precipitate with water before estimating it quantitively

Posted by Basti Raj 6 years, 1 month ago

CBSE > Class 12 > Chemistry

1 answers

Neha Choudhary 6 years, 1 month ago

So that if any residue or substance remained adsorbed on the surface of it is washed away

ANSWER

Important Conversions in Organic Chemistry

Posted by Saksham Chugh 6 years, 1 month ago

CBSE > Class 12 > Chemistry

1 answers

Tamanna Sharma 6 years, 1 month ago

Given in NCERT only

ANSWER

How prepare for organic chemistry ?

Posted by Naresh Kanwar 6 years, 1 month ago

CBSE > Class 12 > Chemistry

4 answers

Priya Dharshini ? 6 years, 1 month ago

Preapre name reactions and distinguish test of all molecules and few questions of text book.. that is enough..

Shri Krishna 6 years, 1 month ago

Firstly prepare the named reaction

Bharti Dabas 6 years, 1 month ago

First of all learn all the name reactions and after that revise important conversions that's it

Bhavesh Joshi 6 years, 1 month ago

If you are having problems in it you mainly focus on name reactions, conversions, mechanism and distinguish. Prepare last 2 chapters well.

ANSWER

Calculate the e cell of the following reaction at298k

Posted by Aadil Tasleem 6 years, 1 month ago

CBSE > Class 12 > Chemistry

1 answers

Tamanna Sharma 6 years, 1 month ago

Dude rxn to lekh

ANSWER

Fuel cell is made up of hydrogen and oxygen electrodes or any combustion reaction and fuel cells are demand of the future. Write the reaction taking place at cathode of the fuel.?

Posted by Jagjit Bains 6 years, 1 month ago

CBSE > Class 12 > Chemistry

1 answers

Adi Kumar 6 years, 1 month ago

O2+ 2H2O+4e=4OH-

ANSWER

Do you have the marks weightage list of every chapters in chemistry?

Posted by Nishtha Maurya 6 years, 1 month ago

CBSE > Class 12 > Chemistry

4 answers

Adi Kumar 6 years, 1 month ago

First book 42 marks . Second book 28 marks

Bhavesh Joshi 6 years, 1 month ago

Officially cbse hasn't declared chapter wise weightage. It has given distribution on the bases of physical, inorgraic and organic units

Abdeali Najmi 6 years, 1 month ago

Yes i have

Aditya Chauhan 6 years, 1 month ago

You Can search on internet

ANSWER

Name reactions

Posted by Dharamveer Sharma 6 years, 1 month ago

CBSE > Class 12 > Chemistry

1 answers

Santosh Kumar 6 years, 1 month ago

Wurtz rxn, friedel-craft rxn, kolbe electrolytic, Williamson synthesis, clemmensen reduction, Rosenmund rxn, cannizzaro rxn, tischenko rxn, aldol condensation, benzoin condensation, haloform rxn

ANSWER

we know that hydrogen is brunt in fire and Oxygen Supply can be used for combustion then how water is able to reduce fire?......??..can anybody answer this Question ..if anybody give the correct explanation then I salute him/her from my heart ??????

Posted by Tamanna Sharma 6 years, 1 month ago

CBSE > Class 12 > Chemistry

11 answers

Aditya Chauhan 6 years, 1 month ago

Is it rubbish i was just giving respect and i just like u nothing but i am very very sorrry i will mind my language and uninstall the apk sorru sorry sorry

Aditya Chauhan 6 years, 1 month ago

Your welcome Sorry for rubbish posting dont insult like that??

Tamanna Sharma 6 years, 1 month ago

Good try to explain but I am not satisfied and secondly I am not Mrs Tamanna,I am only Tamanna sharma so just mind your language and don't comment these rubbish things in chatbox but afterall thanks for your answer ?

Aditya Chauhan 6 years, 1 month ago

Just dont report please

Aditya Chauhan 6 years, 1 month ago

I am in your neighbourhood and have crush on you for you only i typed this much can you.....

Aditya Chauhan 6 years, 1 month ago

Hello Mrs. Tammana these are your quetions on my answer but i have answer to this quetion also..................... Water is able to absorb heat - without increasing much in temperature - better than many substances. This is because for water to increase in temperature, water molecules must be made to move faster within the water; this requires breaking hydrogen bonds, and the breaking of hydrogen bonds absorbs heat.

Tamanna Sharma 6 years, 1 month ago

My genuine question is how water is able to reduce these conditions like temperature etc

Aditya Chauhan 6 years, 1 month ago

To understand how water extinguishes fire, one must first understand what fire is. Fire is the rapid chemical reaction causing emmense amounts of heat and flame. This is classified by the Fire Triangle- Fuel, Heat and Catalyst.. If you remove one of these things, the Fire goes out. This stops the chemical reaction, henc extinguishing the flame. Water helps extinguish fire in two ways. As mentioned above, Water reduces the tempurature of the fuel, removing one of the elements of the fire triangle (fuel, heat, and oxygen). Also, if applied in large amounts, water seperates the fuel from it's catalyst, oxygen, hence removing a second arm of the triangle. Interesting tidbit- Fire is the same chemical reaction as Rust, just a whole load quicker

Tamanna Sharma 6 years, 1 month ago

What happen between fire and water

Tamanna Sharma 6 years, 1 month ago

Rahul kumar, I want to know about the' property ' you say.as in your answer

Rahul Kumar 6 years, 1 month ago

Water is a compound of hydrogen and oxygen, and the property of a compound can be different from its constituent elements

ANSWER

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