No products in the cart.

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

Ask Question
  • 1 answers

Yogita Ingle 4 years, 11 months ago

ess's law of constant heat summation:
                         The law states that the change in enthalpy for a reaction is the same whether the reaction takes place in one or a series of steps. The Hess's law can also be stated as the enthalpy change for a chemical reaction is the same regardless of the path by which the reaction occurs.

For example, consider following two paths for the preparation of methylene chloride
Path I :
CH4​(g)+2Cl2​(g)→CH2​Cl2​(g)+2HCl(g)   ΔH10​=−202.3kJ

Path II :
CH4​(g)+Cl2​(g)→CH3​Cl(g)+HCl(g)ΔH20​=−98.3kJ
CH3​Cl(g)+Cl2​(g)→CH2​Cl2​(g)+HCl(g)ΔH30​=−104.0kJ
Adding two steps
CH4​(g)+2Cl2​(g)→CH2​Cl2​(g)+2HCl(g)         ΔH20=−202.3kJ
Thus whether we follow path I or path II, the enthalpy change of the reaction is same. ΔH10​=ΔH20​+ΔH30​=−202.3kJ

  • 3 answers

Pk ⚔️ 4 years, 11 months ago

Yeah I knw.... congratulation

P Singh . 4 years, 11 months ago

Kafi coding sikh gai ho? keep it up aur batao padhai kaise chal rahi hai???

P Singh . 4 years, 11 months ago

Wow sis.. AMAZING ???
  • 1 answers

P Singh . 4 years, 11 months ago

Good afternoon bhai ?.....kaise ho???
  • 1 answers

Gaurav Seth 4 years, 11 months ago

The chlorine to oxygen bond distance in ClO4​− is 1.44A∘. From this, we can conclude that there must be a considerable double bond character in the bonds.

Ans

From its resonating structure, it can be seen that it have considerable double bond character in the bonds.

Hence, the statement is correct.

  • 1 answers

Gaurav Seth 4 years, 11 months ago

Sulfur hexafluoride is a common example of an octahedral molecule. The central sulfur atom is bonded to six fluoride atoms. In molybdenum hexacarbonyl, a central molybdenum atom is bonded to six carbonyl groups.

  • 1 answers

Yogita Ingle 4 years, 11 months ago

In the periodic table, elements with similar properties are repeated after intervals of 2, 8, 18, 32 etc. These numbers are called magic numbers.

  • 1 answers

Abhay Verma 4 years, 11 months ago

No. of moles =52 Then =52×6.022×10^23 =313.144 ×10^23 =3.13144×10^25 atoms
  • 2 answers

Aman Tripathi 4 years, 11 months ago

HSO4- is a base on the other side of equation - it is the thing that ACCEPTS the proton, so it would act as a BASE. It is the conjugate base of H2SO4. H2SO4/HSO4- is an acid/conjugate base pair. H20 is the base in the forward rxn, because it accepts a proton, and becomes H3O+. An acid and a base which differ only by the presence or absence of a proton are called a conjugate acid-base pair. Thus NH3 is called the conjugate base of NH4+, and NH4+ is the conjugate acid of NH3. Similarly, HF is the conjugate acid of F–, and F– the conjugate base o

Meghna Thapar 4 years, 11 months ago

HSO4- is a base on the other side of equation - it is the thing that ACCEPTS the proton, so it would act as a BASE. It is the conjugate base of H2SO4. H2SO4/HSO4- is an acid/conjugate base pair. H20 is the base in the forward rxn, because it accepts a proton, and becomes H3O+. An acid and a base which differ only by the presence or absence of a proton are called a conjugate acid-base pair. Thus NH3 is called the conjugate base of NH4+, and NH4+ is the conjugate acid of NH3. Similarly, HF is the conjugate acid of F–, and F– the conjugate base of HF.

  • 2 answers

Gaurav Seth 4 years, 11 months ago

<hr />

In a chemical reaction, the species which loses electrons is said to be oxidised and the species which gains electrons is said to be reduced. Since there is no net loss or gain of electrons in a chemical reaction, it means that a substance can gain electron only if another substance that can lose electron is also present in the system. Similarly, a substance can lose electrons only if another substance which can gain electrons is also present in the system. This means oxidation can take place only if reduction also takes place simultaneously and vice versa. In other words, oxidation-reduction reactions are electron transfer processes and always occur side by side. Such reactions in which oxidation and reduction take place simultaneously are called oxidation-reduction or simply redox reactions. For example, consider the following reaction:


This reaction consists of two distinct simultaneous processes which take place in such a way that 

No. of electrons lost  = No. of electrons gained
(i) Oxidation half-reaction:

Here each atom of zinc loses two electrons and thus gets oxidised to Zn2+ ions.
(ii)  Reduction half-reaction:


Thus, a redox reaction may also be defined as a reaction in which electrons are transferred from one reactant to the other.

Ganesh Sherkar 4 years, 11 months ago

BAMS ebe
  • 0 answers
  • 1 answers

Yogita Ingle 4 years, 11 months ago

The ratio of kinetic energy and potential energy of an electron in a Bohr orbit of a hydrogen-like series is -1/2

  • 2 answers

Pk ⚔️ 4 years, 11 months ago

Oh...sorry GST mtlb....anyway iska koi answer nahi hai....pichle kuch dino se hamesa active rah raha hu.....I mean jab bhi phone liyea yek bar check karte hai ki apne dosto ka msg hai ki nahi? ...ok jao padho doctor madam....byee

Pk ⚔️ 4 years, 11 months ago

Left it....koi disturbance to nahi hai naa padhai me....social media....I hope aisa koi disturbance nahi hai.....I tell you agar ghar pe concentrate hoke padho to hostel se jada padh logi....padhai me koi disturbance ho to use manage karo.....11th January last tak complete ho jana chahiyea.......aur maine kab boring bola.....name change karo but uske liye hame doshi mat banao
  • 2 answers

Pk ⚔️ 4 years, 11 months ago

Dushra account banaye raho block hone wali ho????? Time pass kar rahe hai or kya.....

Pk ⚔️ 4 years, 11 months ago

Hath math jodo...hame pap lagega ..... tumhare ashirwad bana rahe bas...
  • 3 answers

Pk ⚔️ 4 years, 11 months ago

Yaha itna pandemic nahi hai....safe hi hai.....tumhe to sabki yad ati hai? mom bhi achi hai.....baki bhaiya ka exam to bhaiya hi Jane ......aaj kal pubg ke sikar hua hai....padhai bas dikhane ke liyea.....hamse bolte hai ki patna chalne ke bad padhenge.....

Pk ⚔️ 4 years, 11 months ago

Good....aur ghar me sab thik hai....chotu kaise hai....padhai karta hai ya sirf badmashi

Pk ⚔️ 4 years, 11 months ago

Mtlb abhi tak hostel join nahi ki ho phir bhi itna din bad ??....seraj bol raha tha ki tum hostel chali gai ho???
  • 2 answers

Pk ⚔️ 4 years, 11 months ago

Hello....I miss you very much....sach me yrr bahot miss kiya maine....waise hostel me phone kaise mila???....chodo aur batao padhai kaise chal rahi hai???

Meghna Thapar 4 years, 11 months ago

In chemistry, resonance is a way of describing bonding in certain molecules or ions by the combination of several contributing structures into a resonance hybrid in valence bond theory.  Resonance structures: Is defined as difference between actual bond energy and energy of most stable resonating structures. Resonance averages the bond characteristics of a molecule as a whole. Resonance stabilizes the molecule because energy of the resonance hybrid is less than the energy of any canonical forms.

  • 0 answers
  • 1 answers

Shikhar Dwivedi 4 years, 11 months ago

A
  • 4 answers

Pk ⚔️ 4 years, 11 months ago

Moch aai hai .....kaise??? Fracture to nahi hai na?.....ulta has rahi ho.....

Pk ⚔️ 4 years, 11 months ago

Yeah your name is familiar?......how r u

Harman Singh 4 years, 11 months ago

[BOND ORDER]co=3

Yogita Ingle 4 years, 11 months ago

Species CO (14), contain bonding electrons =10 and antibonding electrons = 4. 

Bond order =(Nb​−Na)/ 2 ​​= (10−4​)/2 = 3.

  • 1 answers

Divyansh Vohra 4 years, 11 months ago

What
  • 4 answers

Divyansh Vohra 4 years, 11 months ago

Electronegativity is defined as tendency of an electron to attract its shared pair electrons in a chemical bond

Lipika Yadav 4 years, 11 months ago

Electronegativity, symbol χ, measures the tendency of an atom to attract a shared pair of electrons. An atom's electronegativity is affected by both its atomic number and the distance at which its valence electrons reside from the charged nucleus.

Aryan Choudhary 4 years, 11 months ago

The tendency of an atom in a molecule to attract the shared pair of electrons towards itself is known as electronegativity.

Akash Pandey 4 years, 11 months ago

The tendency of an atom in a molecule to attract the shared pair of electrons towards itself is known as electronegativity.
  • 1 answers

Gaurav Seth 4 years, 11 months ago

let atomic weight of x = Mx
atomic weight of y = My

we know,
mole = weight /atomic weight
a/c to question,

mole of xy2 = 0.1
so,
0.1 = 10g/( Mx +2My)

Mx + 2My = 100g -------(1)

for x3y2 ; mole of x3y2 = 0.05

0.05 = 9/( 3Mx + 2My )

3Mx + 2My = 9/0.05 = 9× 20 = 180 g ---(2)
solve eqns (1) and (2)

2Mx = 80
Mx = 40g/mol

and My = 30g/mole

  • 1 answers

Yogitha Sanga 4 years, 11 months ago

Oxygen is a chemical element – a substance that contains only one type of atom. Its official chemical symbol is O, and its atomic number is 8, which means that an oxygen atom has eight protons in its nucleus.
  • 2 answers

Yogitha Sanga 4 years, 11 months ago

Transition elements are those elements in which the atoms or ions (in stable oxidation state) contain partially filled d-orbital. These elements lie in the d-block and show a transition of properties between s-block and p-block. Therefore, these are called transition elements.

Vansh Duggal 4 years, 11 months ago

The elements present between s block and p block which shows transition frm metals to non metals.?
  • 1 answers

Gaurav Seth 4 years, 11 months ago

Molecules -

 

1. Molecules refers to combinations for more than 1 atom.

2. A molecule is molecular level and have its chemical properties.

3. It is at the chemical level that represents chemical properties of that element through out the reaction.

 

Particles -

 

1. Particles are not clear word in their sense. Particles refer to any assumed small thing that exist

2. It is not necessary that a particle have its own chemical properties.

3. It is not chemical level of organisation. It can be notices with nacked eyes or using simple microscope.

  • 0 answers
  • 2 answers

Tanya Rawat 4 years, 11 months ago

Because of high nuclear charge and less negative charge

Gaurav Bharti 4 years, 11 months ago

Hat
  • 3 answers

Aashiya Shaik 4 years, 11 months ago

The physical and chemical properties of elements are the periodic functions of atomic numbers

Divyansh Agrawal 4 years, 11 months ago

The modern periodic law was given by mossile then according to this law the phisical and chemical propertors are based on the peeiodicity of their increasing atomic numbers

Pk ⚔️ 4 years, 11 months ago

Gm bhai
  • 0 answers

myCBSEguide App

myCBSEguide

Trusted by 1 Crore+ Students

Test Generator

Test Generator

Create papers online. It's FREE.

CUET Mock Tests

CUET Mock Tests

75,000+ questions to practice only on myCBSEguide app

Download myCBSEguide App