CBSE > Class 12 > Chemistry | CBSE Board | Homework Help

Ask questions which are clear, concise and easy to understand.

Ask Question

What happens when methyl chloride is treated with AgNo3

Posted by Shruti Dongre 6 years, 9 months ago

3 answers

Sanskriti S 6 years, 9 months ago

in case it is treated with AgNO2, ppt. is formed because NO2- is a good nucleophile & can generate Cl-, whereas NO3- is a poor nucleophile

2Thank You

Sanskriti S 6 years, 9 months ago

Nothing will happen. White ppt. of AgCl is not obtai ed unless methyl chloride is treated with alcohol or any other compound to give halide ion(Cl-). This Cl- then reacts with Ag+ to give AgCl.

1Thank You

Nishtha Ag 6 years, 9 months ago

It's nucleophilic substitution reacn . When CH3Cl react with AgNO2 it will form CH3NO2 +AgCl

0Thank You

ANSWER

Write the rate equation for the reaction A2 + 3 b2 is equal to to see if the overall order of the reaction is zero

Posted by Vishal Mittal 6 years, 9 months ago

CBSE > Class 12 > Chemistry

0 answers

ANSWER

Why S2 is paramagnetic in nature

Posted by Pankaj Kumar 6 years, 9 months ago

CBSE > Class 12 > Chemistry

1 answers

Sanskriti S 6 years, 9 months ago

on the basis of molecular orbital theory, S2 has two unpaired e-s in antibonding pie* orbital (similar to that of O2), so it 8s paramag.

2Thank You

ANSWER

how should i study metallurgy?

Posted by Vanshita S 6 years, 9 months ago

CBSE > Class 12 > Chemistry

1 answers

Pankaj Kumar 6 years, 9 months ago

You should learn all the process given in chapter with there rxn of extraction

2Thank You

ANSWER

Can i leave the derivations of formulas in electrochemistry,chemical kinetics, solutions for boards. Are those derivations asked in boards or only numericals based on those formulas

Posted by Ayushi Kachhwaha 6 years, 9 months ago

CBSE > Class 12 > Chemistry

5 answers

G K 6 years, 9 months ago

Sanskriti*

0Thank You

G K 6 years, 9 months ago

Ryt sanskr5

2Thank You

Sanskriti S 6 years, 9 months ago

well derivations are never asked.. bt physics ka paper dekh k to... kya pta jo phle 10 saal me kabhi ni poocha wo bhi pooch le?

5Thank You

Shivam Keshri 6 years, 9 months ago

Focus on numericals...derivations are not asked from solutions or electochemistry....maybe one or two derivations may be asked fron kinetics but itna chalta hai?✋

1Thank You

Muskan Saxena 6 years, 9 months ago

No , they are very important you have to learn all derivations + numericals ! Nobody knows about the ppr but make sure that you know each n every thing that may be asked in your boards

3Thank You

ANSWER

Which of the following electrolytes is the most effective for the coagulation of Fe(OH)3 sol which is a positively charged sol?NaCl,Na2SO4,Na3PO4

Posted by Tashi Ongmu Lepcha 6 years, 9 months ago

CBSE > Class 12 > Chemistry

3 answers

Yashika Moudgil 6 years, 9 months ago

Acc.to hardy schluze law more would be the charge on ion mote will be its coagulating property so na3po4 has more charge i.e.+3

0Thank You

Sanskriti S 6 years, 9 months ago

Na3PO4(Hardy-Schulze rule)

2Thank You

Tashi Ongmu Lepcha 6 years, 9 months ago

Someone pl??s answer this one

0Thank You

ANSWER

What is the distance between Na+ and Cl_ ions in NaCl crystals if its density is 2.165 gcm_3 [ atomic mass of Na = 23,Cl= 35.5 ]

Posted by Parag Mukherjee 6 years, 9 months ago

CBSE > Class 12 > Chemistry

0 answers

ANSWER

About abnormal molar mass

Posted by Prince Soni 6 years, 9 months ago

CBSE > Class 12 > Chemistry

2 answers

Yogita Ingle 6 years, 9 months ago

Abnormal molar mass : When the molecular mass of a substance as determined by studying any of the colligative properties is different than the theoretically expected value, then the substance will have abnormal molecular mass.

0Thank You

Suhani Rana? 6 years, 9 months ago

It is the molar nass of substsnce when it shows association and dissiciation in solvent.

1Thank You

ANSWER

Can order of reaction be zero ? Give example.

Posted by Abhay Upadhyay 6 years, 9 months ago

CBSE > Class 12 > Chemistry

2 answers

Yogita Ingle 6 years, 9 months ago

If the rate of reaction is independent of concentration of the reactant participating in the reaction then the reaction is called Zeroth order reaction.

0Thank You

Sneha Bansal 6 years, 9 months ago

Yes zero order reactions are possible e.g. It is a experimental parameter.

1Thank You

ANSWER

Why are substances like platinum and palladium often used for carrying out electrolysis of aqueous solutions?

Posted by Shivam Keshri 6 years, 9 months ago

CBSE > Class 12 > Chemistry

1 answers

Yogita Ingle 6 years, 9 months ago

Due to the following features:
(i) Chemical inertness Both form chemically inert electrodes.
(ii) Adsorption capacity Platinum and palladium both have good adsorptive capacity for hydrogen.

1Thank You

ANSWER

What are the Important questions in chapter chemistry in everyday life class12

Posted by Sachin Yadav 6 years, 9 months ago

CBSE > Class 12 > Chemistry

1 answers

Ayushi Kachhwaha 6 years, 9 months ago

Names of all medicines and other examples given

0Thank You

ANSWER

Why element will show higher oxidation state with flourine and oxygen only ?

Posted by Pankaj Kumar 6 years, 9 months ago

CBSE > Class 12 > Chemistry

1 answers

Raghvendra Khatri 6 years, 9 months ago

Because F and O are the most electronegative elements that why elements show high oxidation state with O nad F

1Thank You

ANSWER

why is the decomposition of hydrogen peroxide in presence of iodide ion a first order reaction

Posted by Varun Upreti 6 years, 9 months ago

CBSE > Class 12 > Chemistry

0 answers

ANSWER

What is meant by overpotential of oxygen in electro chemistry??

Posted by Gaurav Sharma 6 years, 9 months ago

CBSE > Class 12 > Chemistry

0 answers

ANSWER

Why preparation of ether by acid dehydration of secondary and tertiary alcohol is not a suitable method???

Posted by Nishtha Ag 6 years, 9 months ago

CBSE > Class 12 > Chemistry

0 answers

ANSWER

Bleaching of flowers by chlorine is permanent while that by sulphur dioxide is temporary. Why?

Posted by Lokesh Ramadas 6 years, 9 months ago

CBSE > Class 12 > Chemistry

3 answers

Sanskriti S 6 years, 9 months ago

bleaching action of SO2 is due to reduction(nascent [H]). When the bleached substance is exposed to air(O2), it again gets oxidised, ie, coloured. Whereas bleaching action of Cl2 is due to oxidation([O]), which cannot be reversed in presence of air.

3Thank You

Suraj Choudhary 6 years, 9 months ago

Because when chlorine is treated with water it produces nascent oxygen which combines with colour substance and then oxide into colourless substance this property doesn't hold for Sulphur Dioxide that's why bleaching of flower by chlorine is permanent while then by Sulphur dioxide is temporary

0Thank You

Gaurav Sharma 6 years, 9 months ago

What do you mean by flower

2Thank You

ANSWER

What is reactivity order of sn1 and sn2

Posted by Ankit Singh 6 years, 9 months ago

CBSE > Class 12 > Chemistry

4 answers

Ankit Singh 6 years, 9 months ago

1>2>3> and 3>2>1

0Thank You

Dipti Santani 6 years, 9 months ago

Because reactivity of SN1 increases and SN2 decrease

0Thank You

Dipti Santani 6 years, 9 months ago

SN1=1>2>3 and SN2= 3>2>1

1Thank You

Sangeeta Nara 6 years, 9 months ago

Sn1=3>2>1 ....Sn2=1>2>3

0Thank You

ANSWER

What is SN1 and SN2 reaction difference

Posted by Sanna Arora 6 years, 9 months ago

CBSE > Class 12 > Chemistry

3 answers

Nishtha Ag 6 years, 9 months ago

Sn1 is unimolecular while SN2 is bimolecular Sn1 mechanism are the racemic mixture because nucleophile can attack on the same side or opposite side while SN2 has inverted configuration

0Thank You

Dipti Santani 6 years, 9 months ago

SN2 is backside attack and SN1 is front side

1Thank You

Ankit Singh 6 years, 9 months ago

Sn1 is biomolecular and sn2 unimoleculor

1Thank You

ANSWER

Difference between p type and n type semiconductor

Posted by Rahul Pal 6 years, 9 months ago

CBSE > Class 12 > Chemistry

2 answers

Suraj Choudhary 6 years, 9 months ago

N is a carier of electrons and P is the carier of holes

0Thank You

Bhawan Preet 6 years, 9 months ago

p type has majority holes and n type has electrons

3Thank You

ANSWER

5methyl4methonol3methylcholridehexane

Posted by Aashutosh Kr. Modi 6 years, 9 months ago

CBSE > Class 12 > Chemistry

0 answers

ANSWER

What is molality normality and morality

Posted by Wani Mehnaj 6 years, 9 months ago

CBSE > Class 12 > Chemistry

1 answers

Suhani Rana? 6 years, 9 months ago

Molality is defined as the number of moles of solute dissolve in 1L of solvent. Molarity is defined as the no of moles of solute dissolve in 1 kg of solution. Normality is defined as no of mole equivalent per litre of solution.

1Thank You

ANSWER

How will the ph of brine (aq. Nacl solution) be affected when it is electrolysed

Posted by Shivani Singh 6 years, 9 months ago

CBSE > Class 12 > Chemistry

1 answers

Harshita Panwar 6 years, 9 months ago

ph will increased due to formation of NaOH

0Thank You

ANSWER

An element has a body -centred cubic (BBC) structure with a cell edge of 288pm. The density of the element is 7.2g/ centimetre cube dot how many atoms are present in 2 08 g of element

Posted by Pramod Singh 6 years, 9 months ago

CBSE > Class 12 > Chemistry

1 answers

Suhani Rana? 6 years, 9 months ago

In BCC Z=2 so using formula d=z×W/a^3×N we can find N

0Thank You

ANSWER

Three rxn of glucose which cannot be explained by its chain structures

Posted by Pankaj Kumar 6 years, 9 months ago

CBSE > Class 12 > Chemistry

1 answers

Aayushi Srivastava 6 years, 9 months ago

objection against straight chain structure if glucose are.. it diesnot react with Schiff reagent.....pentacetate of glucose doesnot react with hydroxylamine....it doesnot form 2-4dnp derivatives....

0Thank You

ANSWER

Structure of an isomer of compound c4h9br

Posted by Harsh Chhillar 6 years, 9 months ago

CBSE > Class 12 > Chemistry

1 answers

Lokesh Ramadas 6 years, 9 months ago

1-bromobutane and 2-bromobutane

1Thank You

ANSWER

How will you prepare 2 hydroxybenzoic acid from carboxylic acid

Posted by Sreenidhi A 6 years, 9 months ago

CBSE > Class 12 > Chemistry

1 answers

Lokesh Ramadas 6 years, 9 months ago

It is more or less similar to preparation of salicylic acid.

0Thank You

ANSWER

A compound forms hexagonal close packed structure. What is total number of voids in 0.5 mol of it? How many of these are tetrahedral voids?

Posted by Chetna Maheshwari 6 years, 9 months ago

CBSE > Class 12 > Chemistry

1 answers

Amanpreet Aulakh 6 years, 9 months ago

No. Of unit cell=0.5×Na No. Of tv= 2×0.5×Na No. Of Ov=0.5×Na Total voids=1.5×Na

0Thank You

ANSWER

Why rate of reaction double with 10° rise in temperature

Posted by Ishita Jain 6 years, 9 months ago

CBSE > Class 12 > Chemistry

1 answers

Harsh Chhillar 6 years, 9 months ago

When the temperature is incresed to t+10 then the fraction of molecules having kinetic energy greater than threshold value then rate of rxn double It is mainly because due to increase in no of effective collisons

1Thank You

ANSWER

What are antioxidants? What are they used for?

Posted by Snehashish Datta 6 years, 9 months ago

CBSE > Class 12 > Chemistry

2 answers

Yogita Ingle 6 years, 9 months ago

Substances that inhibit the oxidation of other molecules are called antioxidants.
Antioxidants are widely used in dietary supplements and these are very important for the prevention of many diseases that include cardiac disorders and cancer.
The other uses of antioxidants include application in industry for controlling reactions, food preservatives and cosmetics.

1Thank You

Pratiksha Tiwari 6 years, 9 months ago

They retard the action of oxygen on the food and help in preservation

3Thank You

ANSWER

what is the weightage of metallurgy i.e. general pricipals of isolation of elements chapter

Posted by Dharshika As 6 years, 9 months ago

CBSE > Class 12 > Chemistry