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Explain synthetic resins method.

Posted by Divya Tripathy 7 years ago

CBSE > Class 11 > Chemistry

1 answers

Yogita Ingle 7 years ago

Synthetic resins method is a method used for removing permanent hardness of water. In this method ion exchange resins (RSO₃H) is changed to RNa by treating it with NaCl. Then, RNa exchanges Na⁺ ions with Ca²⁺ and Mg²⁺ ions present in hard water and as a result, hard water is softened.
2RNa + M²⁺ → R₂M + 2Na⁺
R₂M + 2 NaCl → 2RNa + MCl₂

ANSWER

What is Sigma or Pi bond?

Posted by Dhan Raj 7 years ago

CBSE > Class 11 > Chemistry

6 answers

Ankit Singh 7 years ago

Maths student

Ayushi Ayushi 7 years ago

Thanks . I am a science (non- medical ) student.

Aman Kumar 7 years ago

Nicely explained ......are you a computer CS student or bio stud.??

Ayushi Ayushi 7 years ago

for example methane molecule contain 4 C-H sigma bonding. . For example, ethylene molecule contain 5 sigma bonding and 1 pi bonding in it.

Ayushi Ayushi 7 years ago

Sigma And Pi Bonds. A sigma bond is a covalent bond which is formed by the head on overlap of two atomic orbitals. The combination of overlapping orbitals can be s-s, s-pz or pz-pz. ... A Pi bond is a covalent bond which is formed by the side-to-side overlap of two atomic orbitals.

Aman Kumar 7 years ago

Single bond is Sigma bond and double bond is Pi bond

ANSWER

Why nitrogen is highly reactive?

Posted by Tejasvani Chauhan 7 years ago

CBSE > Class 11 > Chemistry

3 answers

Priya Dharshini ? 7 years ago

Nitrogen is low reactive. If it is highly reactive than our ozone layer would be completely depleted

Priya Dharshini ? 7 years ago

Due to small size and more electronegative character of nitrogen, there is p(pi) - p(pi) interaction between the two atoms and all the electrons in the valance shell are involved in the triple bond. Due to this strong triple bond formation, bond enthalpy of nitrogen is very high. Thus, Nitrogen gas has low reactivity.

Tejasvani Chauhan 7 years ago

It has triple bond to form N2 so if it was reactive then it could react with other gases and depleted our ozone layer.

ANSWER

Why co2 is inorganic compound it is also made from carbon then??

Posted by Garima Kesherwani 7 years ago

CBSE > Class 11 > Chemistry

1 answers

Ayushi Ayushi 7 years ago

The answer is because organic molecules don't just contain carbon. They contain hydrocarbons or carbon bonded to hydrogen. The C-H bond has a lower bond energy than the carbon-oxygen bond in carbon dioxide, making carbon dioxide more stable/less reactive than the typical organic compound.

ANSWER

Be2 molecule does not exist

Posted by Rohit Kumar 7 years ago

CBSE > Class 11 > Chemistry

2 answers

Janvi Malhotra 7 years ago

Beryllium molecule is also not possible because according to valence bond theory the number of repulsive forces is more than the number of attractive forces.So Be2 is not possible

Ayushi Ayushi 7 years ago

Answer The electronic configuration of Beryllium is 1s2 2s2. From the electronic configuration it is clear that there is no singly filled atomic orbital present in beryllium. Without the half filled orbital,the overlapping is not possible ,therefore Be2 molecule does not exist.

ANSWER

Isolated gaseous atom

Posted by Subhi ? 7 years ago

CBSE > Class 11 > Chemistry

5 answers

Vipul Chaudhary 7 years ago

It is used ,when energy is giving to take an electron or electron enter to the shell if it not isolated we have to give more energy or less energy to evolve that electron
And thus affect our calculation
So term isolated gaseous atom in it ground state is used

Ayushi Ayushi 7 years ago

Your wellcome.

Subhi ? 7 years ago

Thanks✌✌

Ayushi Ayushi 7 years ago

the term 'isolated gaseous atom' is used in the definition of ionization enthalpy. Ground state of an atom refers to the most stable state of an atom. If an isolated gaseous atom is in its ground state, then less amount energy would be required to remove an electron from it.

Ayushi Ayushi 7 years ago

An isolated atom is an atom with the same number of electron as protons yeilding a net charge of 0. The properties of an atom in isolation is different from that of individual atoms in relatively close proximity to each other. ... Thus, atoms are almost always found associated in some way with other atoms.

ANSWER

What is electron gain enthelpy

Posted by Gopal Sharma Manju Goswami 5 years, 8 months ago

CBSE > Class 11 > Chemistry

1 answers

Ayushi Ayushi 7 years ago

Electron gain enthalpy is defined as the amount of energy released when an electron is added to an isolated gaseous atom. During the addition of an electron, energy can either be released or absorbed. Sign Convention For Electron Gain Enthalpy: Negative: When energy is released while accepting an electron. Positive: When energy is supplied to an atom while adding an electron.

ANSWER

Iso-electronic species defination

Posted by Rohit Kumar 7 years ago

CBSE > Class 11 > Chemistry

1 answers

Yogita Ingle 7 years ago

Species (atoms or ions) with same number of electrons are called iso-electronic species.
Number of electrons in Cl⁻ = 17+1 = 18

Atom	Atomic number	Ion	Number of electrons
Sulphur	16	S⁻²	16 + 2 = 18
Potassium	19	K⁺¹	19 - 1 = 18

ANSWER

Why 1 litre of hydrogen peroxide gives 10 litre of oxygen???

Posted by Satyam Singh 7 years ago

CBSE > Class 11 > Chemistry

0 answers

ANSWER

Chapter hydrogen question 15 is wrong

Posted by Jassi Ji 7 years ago

CBSE > Class 11 > Chemistry

0 answers

ANSWER

How can we define electronegetivity in periodic table

Posted by Ayushi Nigam 7 years ago

CBSE > Class 11 > Chemistry

1 answers

???. Pragati 7 years ago

The positively charged protons in the nucleus attract the negatively charged electrons. As the number of protons in the nucleus increases, the electronegativity or attraction will increase. Therefore electronegativity increases from left to right in a row in the periodic table

ANSWER

Formula of urea?

Posted by Santosh Bishnoi 7 years ago

CBSE > Class 11 > Chemistry

6 answers

Priya Dharshini ? 7 years ago

Thank u ankit and ✌✌❤(dnt know ur name)

Ankit Singh 7 years ago

CH4N2O

Ankit Singh 7 years ago

Happy birthday Priya

???. Pragati 7 years ago

CH4N2O

???. Pragati 7 years ago

Happy birthday priya

Priya Dharshini ? 7 years ago

CH4N2O is formula for urea

ANSWER

two different compounds a and b containing nitrogen and oxygen were found to have 63.6% and 46.7% of nitrogen respectively. show that the data illustrates the law of multiple proportion

Posted by Lavi Ghotra 7 years ago

CBSE > Class 11 > Chemistry

0 answers

ANSWER

Find out tha oxidation state of Fe2O3 and [Ti(H2O)6]

Posted by Gourav Kaushik 7 years ago

CBSE > Class 11 > Chemistry

0 answers

ANSWER

Name the chief factor responsible for the anomalous behaviour of lithium ????

Posted by @@Ditya ®°@Thore????? 7 years ago

CBSE > Class 11 > Chemistry

2 answers

@@Ditya ®°@Thore????? 7 years ago

Thanks Nancy

Nancy Rajput 7 years ago

1)Small size atom and ion, 2)High ionization enthalpy 3)Absence of d-orbital in its Valence shell.

ANSWER

Why does a tube containing lime water turn milky when exhaling is made into it ?????????

Posted by @@Ditya ®°@Thore????? 7 years ago

CBSE > Class 11 > Chemistry

3 answers

Lily ☺ 6 years, 11 months ago

Due to the formation of calcium carbonate.

@@Ditya ®°@Thore????? 7 years ago

Thanks Pragati???

Pragati Gola 7 years ago

CO2+CaO -->CaCO3

ANSWER

what is univalent radicals

Posted by Nancy Rajput 7 years ago

CBSE > Class 11 > Chemistry

2 answers

Priya Dharshini ? 7 years ago

Having valence 1, regardless of whether the valence is positive or

Ankit Singh 7 years ago

Having a valence of one; capable of combining with, or of being substituted for, one atom of hydrogen; monovalent; -- said of certain atoms and radical

ANSWER

the correct IUPAC name of 2-iso-butylbutanamide is

Posted by Nancy Rajput 7 years ago

CBSE > Class 11 > Chemistry

6 answers

Ankit Singh 7 years ago

I can't draw the structure

Ankit Singh 7 years ago

N-(2-methylpropyl)butanamide i know the structure but .........

Aman Kumar 7 years ago

Ab hum kya kar sakte hai....?

Nancy Rajput 7 years ago

i also dont know the answer

Aman Kumar 7 years ago

But u only tell without any structure how can anyone say that the name is correct or not...sooooo.....

Aman Kumar 7 years ago

Is it not correct?

ANSWER

anyone who help me organic chemistry

Posted by Nancy Rajput 7 years ago

CBSE > Class 11 > Chemistry

4 answers

Ankit Singh 7 years ago

Nancy what is the question

Ankit Singh 7 years ago

Yes please telll

Nancy Rajput 7 years ago

there are some structure how i upload here it if jee based question

Aman Kumar 7 years ago

Yah...tell but I know that I m not good in organic than u

ANSWER

Ionic bond of MgO

Posted by Bk Tripathi 7 years ago

CBSE > Class 11 > Chemistry

0 answers

ANSWER

Noble gas have positive electron gain enthalpy.justify

Posted by Rohit Kumar 7 years ago

CBSE > Class 11 > Chemistry

1 answers

Sheeja Menon 7 years ago

It is because noble gases like He, Ne, etc. have a stable electronic configuration. So it is not possible for it to gain any electron. Hence it is having positive electron gain enthalpy.

ANSWER

Whats is the difference between +r effects and - r effects

Posted by Nousin Ahamed 7 years ago

CBSE > Class 11 > Chemistry

3 answers

Aman Kumar 7 years ago

Thanks pragati...for nice answer

Pragati Gola 7 years ago

In -R (-Resonance effect) the electron pair transfers to function group or atom .e.g. -Nitrobenzen . In +R (+Resonance effect) e- pair transfer from functional group which can delocalised e- (s).e.g. -phenol

Aman Kumar 7 years ago

What is r -effect???? I studied about I-effect, E-effect,M-effect,H-effect ......but what about r-effect...

ANSWER

organic reactions

Posted by Sunil Verma 7 years ago

CBSE > Class 11 > Chemistry

1 answers

???. Pragati 7 years ago

Organic reactions are chemical reactions involving organic compounds. The basic organic chemistry reaction types are addition reactions, elimination reactions, substitution reactions, pericyclic reactions, rearrangement reactions, photochemical reactions and redox reactions.

ANSWER

What is halides ?

Posted by Rahul Bodh 7 years ago

CBSE > Class 11 > Chemistry

2 answers

Shailendra Kumar 7 years ago

When s block element are react with halogen form halide

???. Pragati 7 years ago

Answer: Halides are anions of the Group 17 elements, Halides are compounds of Halogens. They consist of a Halogen anion, also called a halide ion and a cation.

ANSWER

Why ClO4– doesn't show disproportionate reaction?

Posted by Divya Tripathy 7 years ago

CBSE > Class 11 > Chemistry

0 answers

ANSWER

Why only Pd( palladium) , Pt ( platinum) and Ni ( nickel) are used as catalyst in chemical reactions??

Posted by Prakhar Jadaun ? 7 years ago

CBSE > Class 11 > Chemistry

1 answers

Gaurav Pandey 7 years ago

Because these metal gave large surface area for reaction to occur very efficiently

ANSWER

what is the functionak group name of cne3

Posted by Nancy Rajput 7 years ago

CBSE > Class 11 > Chemistry

4 answers

Nancy Rajput 6 years, 11 months ago

its Ch3

Nancy Rajput 7 years ago

i also dont knoe

Ankit Singh 7 years ago

Sorry dont ???

Ankit Singh 7 years ago

Please answer this question i also donot know the answer

ANSWER

Why oxidation no of O2F2 is +1 ...why it's not +2

Posted by Subhi ? 7 years ago

CBSE > Class 11 > Chemistry

2 answers

Subhi ? 7 years ago

Define it na ...

Dharmendar Tripathi 7 years ago

Because peroxide case

ANSWER

Find the pH if 10cc 0.1M H2SO4 reacts with 0.1M KOH

Posted by Atman Das 7 years ago

CBSE > Class 11 > Chemistry

1 answers

Sivan Karthick 7 years ago

put in the formula ph=-log(v2/v1)

ANSWER

Is boric acid a protic acid???

Posted by ???. Pragati 7 years ago

CBSE > Class 11 > Chemistry

2 answers

Yogita Ingle 7 years ago

A protic acid is one which can ionise in solution to produce proton or hydronium ion. It is not protic acids since it does not ionise in H₂O to give a proton.
Boric acid is not a protic acid. It accepts a pair of electron from OH^- ion of water and acts as a lewis acid
B(OH)₃ +2H₂0 →[B(OH)₄]^-+H₃O⁺

Ankit Singh 7 years ago

According to their theories , a protonic acid is a species which donate a proton i.e. ... But boric acid do not donate H+ rather it accepts an electron pair from the solution or the donor i.e. an OH-.

ANSWER

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