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What is the difference between Valency and Oxidation number?????

Posted by Rachit Yadav 7 years, 2 months ago

1 answers

Yogita Ingle 7 years, 2 months ago

Valencey	Oxidation Number
1. It is the combining capacity of an element in terms of the number of hydrogen atoms with which the element may combine e.g. valency of S in H₂S is 2 and that of N in NH₃ is 3.	1. It is the charge which an atom of the element has or appears to have when present in the combined state with their atoms e.g. oxidation number of N in HNO₃ is +5.
2. It is purely a number and has no plus or minus sign associated with it. e.g. valency of N in NH₃ is 3 and that of H is 1.	2. It is always assigned plus or minus sign except when it is zero e.g. oxidation number of N in NH₃ is -3 and that of H is +1
3. It is always a whole number.	3. It may not always be a whole number but may be fractional also. The e.g. oxidation number of Fe in Fe₃O₄ is +8/3.

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What is transition elements. Predict the position of the elements in the periodic table satisfying the electronic configuration (n--1)d^1ns^2for n=4.

Posted by Shivshant Upadhyay 7 years, 2 months ago

CBSE > Class 11 > Chemistry

2 answers

Soojal Bhardwaj 7 years, 2 months ago

Classify also on size if we go down the group the last three elements is same on 4-12

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Yogita Ingle 7 years, 2 months ago

Elements which contains incomplete penultimate (d – sub shell) shell with electrons are called transition elements. In transition elements the valency electrons goes to d - sub shell.
These are the metals with high melting and boiling points. They exhibit different oxidation states.
In periodic table they are present in 3d- series (1^st transition series), 4d –series (2^nd transition series), 5d - Series (3^rd transition series) & 6d – series (4^th transition series).

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What is the oxidation no. Of chlorine in CaOCl2

Posted by Shruti Gupta 7 years, 2 months ago

CBSE > Class 11 > Chemistry

1 answers

Yogita Ingle 7 years, 2 months ago

If we take Cao then we will get the oxidation state of calcium Let oxidation state of calcium be xX+1(-2)=0X-2=0X=2
Now we take CaOCl₂ So, 2+1(-2)+2=0X=0
This is the the oxidation state of 2chlorine atoms. If we break CaOCl₂ we will get: Ca(oH)₂+H-ocl+Hcl
In H-ocl,1+1(-2)+x=0X=1(x is the oxidation state of chlorine)
In Hcl, 1+x=0X=-1
This we got the oxidation state of chlorine that is +1and -1

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What is the oxidation no. Of C

Posted by Shruti Gupta 7 years, 2 months ago

CBSE > Class 11 > Chemistry

1 answers

Priya Dharshini ☺☺ 7 years, 2 months ago

So unlike metals, which are almost always in a positive oxidation state, the oxidation state of carbon can vary widely, from -4 (in CH4) to +4 (such as in CO2).

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Electron gain enthalapy of group 17 or halogen family is more negative i.e. highest .Why?

Posted by Shivshant Upadhyay 7 years, 2 months ago

CBSE > Class 11 > Chemistry

1 answers

Soojal Bhardwaj 7 years, 2 months ago

The valence shell electronic configuration of the halogens is ns2np5 and such away they require only single electron to gain the stable noble gas configuration is ns2np6 so there electron gain enthalpies ate highly negative

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What is the value of critical constants (s).

Posted by Shivshant Upadhyay 7 years, 2 months ago

CBSE > Class 11 > Chemistry

0 answers

ANSWER

Why is dipole moment of NH3 is less than NF3

Posted by Shivshant Upadhyay 7 years, 2 months ago

CBSE > Class 11 > Chemistry

3 answers

Shivshant Upadhyay 7 years, 2 months ago

By mistake .OK then tell why is dipole moment of NF3 is less than NH3.

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Manika Gupta 7 years, 2 months ago

Because the resultant dipole moment of NH3 is in same direction while the dipole moment of NF3 is in opposite direction

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Manika Gupta 7 years, 2 months ago

Question wrong hai Correct question is : Why the dipole momemt of NF3 is less than NH3

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When is Z<1 and Z>1 with explanation.

Posted by Shivshant Upadhyay 7 years, 2 months ago

CBSE > Class 11 > Chemistry

1 answers

Ankit Aryan Shivan 7 years, 2 months ago

Z<1than gas show negative deviation.and gas is more compressible than expected from ideal behaviour. Z>1 than gas show +ve deviation. And less compressible.

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What is the ratio of ebym

Posted by Anurag Dwivedi 7 years, 3 months ago

CBSE > Class 11 > Chemistry

0 answers

ANSWER

Calculate the formal charge on each atom of carbonate ion and sulphur dioxide molecules

Posted by Kashish Raza 7 years, 3 months ago

CBSE > Class 11 > Chemistry

0 answers

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What is amorphas

Posted by Supriya Thakur 7 years, 3 months ago

CBSE > Class 11 > Chemistry

1 answers

Yogita Ingle 7 years, 3 months ago

If groups of atoms are not given a chance to average themselves in proper order say by checking their mobility at low temperature, amorphous solids are formed, e.g., amorphous carbon.
The solids in which the constituent particles of matter are arranged in a random manner are called amorphous solids. It is a non-crystalline solid with no proper arrangement of atoms in the solid lattice. In other words, we can define amorphous solids as materials which don’t have certain organized arrangement of atoms and molecules. Most solids are amorphous in nature and are utilized in many sectors as well. One of the most common examples of amorphous solids is glass, which is used widely in the manufacturing sector.

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1erg equal how much joule

Posted by Alok Kumar 7 years, 3 months ago

CBSE > Class 11 > Chemistry

6 answers

Isha Bhardwaj 7 years, 3 months ago

Priya is right.....

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Priya Dharshini ☺☺ 7 years, 3 months ago

Zalak how u got that ans any derivation is there pls let me know

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Priya Dharshini ☺☺ 7 years, 3 months ago

Unit of energy is joule = kg*m²/s² Joule is a MKS unit and erg is a CGS unit MKS = CGS 1 m = 100 cm 1 s = 1 s 1 kg = 1000 gm From above : 1 joule = 1 kg*m²/s² = 1000 * 10000 / 1 cm*m²/s²= 10^7 gm*cm²/s² = 10^7 erg So, Answer : 1 joule = 10^7 erg i got this ans by derivation

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Zalak Patel????️ 7 years, 3 months ago

That is wrong. Right answer is 1*10-5(-5 is in power of 10 means 10 to the power of -5)

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Zalak Patel????️ 7 years, 3 months ago

7 joule

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Priya Dharshini ☺☺ 7 years, 3 months ago

1 × 10^-7 joule i think so this is ans. Verify it once

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Give equation which had been instrumental in discovery of neuron.

Posted by Vaibhavi Patel 7 years, 3 months ago

CBSE > Class 11 > Chemistry

0 answers

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Calculate mole fraction of urea and water if 2g urea dissolved in 31.4g aquous solution.

Posted by Ayush Kumar 7 years, 3 months ago

CBSE > Class 11 > Chemistry

0 answers

ANSWER

What is word root in catecolamine.

Posted by Avantika Sharma 7 years, 3 months ago

CBSE > Class 11 > Chemistry

0 answers

ANSWER

Which of them has stronger intermolecular forces,co2 or water?And why?

Posted by Anurag Pandey 7 years, 3 months ago

CBSE > Class 11 > Chemistry

2 answers

Avantika Sharma 7 years, 3 months ago

Water.because of strong hydrogen bond whereas in co2 weak dispersion forces are present

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Aman Kumar 7 years, 3 months ago

Water bcoz water has more force of attraction than CO2 so... I think inter molecular force is more on water

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What is cantenation(self combination) in carbon.

Posted by Account Deleted 7 years, 3 months ago

CBSE > Class 11 > Chemistry

2 answers

Ankit Aryan Shivan 7 years, 3 months ago

Long. not lomg

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Ankit Aryan Shivan 7 years, 3 months ago

Lomg chain of carbon compound .

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When 430j of work was done on a system. It loose 120j of energy at heat cacluate the value of internal energy changes for these process

Posted by Tushar Anand 7 years, 3 months ago

CBSE > Class 11 > Chemistry

1 answers

Tushar Anand 7 years, 3 months ago

550

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What is oxidised redused

Posted by Aliah Afia 7 years, 3 months ago

CBSE > Class 11 > Chemistry

0 answers

ANSWER

molecular mass

Posted by Manash Dewangan 7 years, 3 months ago

CBSE > Class 11 > Chemistry

1 answers

Account Deleted 7 years, 3 months ago

Molecular mass may be define as total atomic maas of all elements of molecule is called as molecular maas

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What is iupc

Posted by Balraj Sen Srivastava 7 years, 3 months ago

CBSE > Class 11 > Chemistry

3 answers

Ujjwal Tiwari 7 years, 3 months ago

IUPAC- INTERNATIONAL UNION OF PURE APPLIED CHEMISTRY

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Soma Shekar 7 years, 3 months ago

IUPAC-Interantional Union of Pure and Applied Chemistry

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Nidhi Shukla 7 years, 3 months ago

International union of physical and applied chemistry

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Why water is not flameable

Posted by R :) Khatri 7 years, 3 months ago

CBSE > Class 11 > Chemistry

1 answers

Chesta Pawan Manchanda 7 years, 3 months ago

Water is made up of two elements, hydrogen and oxygen. Hydrogen is flammable, but oxygen is not. Flammability is the ability of a combustible material with an adequate supply of oxygen (or another oxidiser) to sustain enough heat energy to keep a fire going after it has been ignited.

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Gay lussaic law

Posted by Vikas Chaudhary 7 years, 3 months ago

CBSE > Class 11 > Chemistry

5 answers

Aman Kumar 7 years, 3 months ago

Good???

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Ʌɐpɐʎ Ɐuɐɥsɹɐp . 7 years, 3 months ago

arrey nhi avi khatam ni hua... bus jinka fear tha mind may vo ho gye. ?

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Aman Kumar 7 years, 3 months ago

Darshana

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Aman Kumar 7 years, 3 months ago

Long time Haann... Hua exam khatam?????

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Ʌɐpɐʎ Ɐuɐɥsɹɐp . 7 years, 3 months ago

Gay Lussac's Law states that at constant volume, pressure of a fixed amount of a gas varies directly with the temperature.

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What is the effect of temperature on viscosity of liquids

Posted by Anshu Yadav 7 years, 3 months ago

CBSE > Class 11 > Chemistry

0 answers

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What is kolby

Posted by Pranav Sharma 7 years, 3 months ago

CBSE > Class 11 > Chemistry

0 answers

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B2 H6 belong to which hydride

Posted by Gauri Dwivedi 7 years, 3 months ago

CBSE > Class 11 > Chemistry

2 answers

Zalak Patel????️ 7 years, 3 months ago

Metallic hydride and electron-deficient

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Kajal Srivastva 7 years, 3 months ago

Hybridusation is only possible for even no of valence electrons .As there are total 9 valence eletrons present so there is no hybrid state .....it is not applicable for odd no of electrons

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What is the empirical formula

Posted by Mradul Goyal 7 years, 3 months ago

CBSE > Class 11 > Chemistry