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  • 1 answers

Manjushree Hiremat 7 years, 11 months ago

You plz check in your manual do the tests given only in ur manual whether it is a detection test or confirmatory test or else there will be possibilities of loosing marks
  • 2 answers

Manjushree Hiremat 7 years, 11 months ago

S

Komal Kundaliya 7 years, 11 months ago

Can you do by an example of ncert
  • 4 answers

Pavan Pandit 7 years, 11 months ago

Same molecular formula but different behavior

Priya Kumari 7 years, 11 months ago

Isomerism is a phenomenon in which two or more compounds has the same chemical formula but show different properties because of different structural arrangement

T K 7 years, 11 months ago

Can u explain it in detail

Bhargit Singh 7 years, 11 months ago

It is a phenomena in which molecules have a same structural formula but different dimensions
  • 2 answers

Pooja Goyal 7 years, 11 months ago

Because iffective nuclear charge on last electron of boron is less due to which it is easy to remove electron from last shell of boron than beryllium and thus ionization energy of boron is less than berrylium

Ravi Pal 7 years, 11 months ago

beryllium has fully filled electrons and half fill & fully filled are more stable
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  • 1 answers

Shubham Mehra 7 years, 11 months ago

Production of ammonia is by born Haber cycle. N2+3H2 --- 2NH3
  • 1 answers

Gurvinder Kaur 7 years, 11 months ago

{tex}PbS(s)+4H_2O_2(aq) \to PbSO_4(s)+4H_2O(l){/tex}

  • 1 answers

Mihir Makwane 7 years, 11 months ago

Lead oxide is used in lead paintings and Lead statues when they expressed to air for long time lead oxide react with hydrogen sulphide which is found in the air and form lead sulphide which is black in colour when lead sulphide reacts with hydrogen peroxide then white lead sulphide is formed and paintings again comes in its original form
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Mihir Makwane 7 years, 11 months ago

Hydrogen peroxide easily decompose to release Oxygen and it acts as a strong oxidizing agent it show oxidizing property in acidic medium as well as basic medium.
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Gurvinder Kaur 7 years, 11 months ago

<th scope="col"> <div>
One is heated in the presence of excess of oxygen or air. one is heated in the absence or limited supply of oxygen or air
This method is employed for sulphide ores. This method is employed for carbonate ores.
Sulphur dioxide is produced along with metal oxide. Carbon dioxide is produced along with metal oxide.
<div>Example: For the ores ZnS (sphalerite)  and Cu2S (chalcocite), balanced equations for the roasting are:</div> <div>{tex}2ZnS+3O_2\to2 ZnO+ 2SO_2{/tex}</div> <div>{tex}2 Cu_2S + 3O_2\to 2 Cu_2O + 2 SO_2{/tex}</div> <div>Example:
{tex} ZnCO_3\to ZnO+ CO_2{/tex}</div>
  • 1 answers

Harsh Rai 7 years, 11 months ago

According to modern periodic law"physical &chemical property of element is based on their atomic no."
  • 2 answers

Rahul Agarwal 7 years, 11 months ago

NA BECAUSE MORE CHARGE ON ANY CATION,LESS IS ITS SIZE

Jai Sharma 7 years, 11 months ago

Na has
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  • 1 answers

Mohit Fdk 7 years, 11 months ago

second law of thermodynamics states that the entropy of any isolated system always increases.
  • 1 answers

Mohit Fdk 7 years, 11 months ago

Application of Hess's Law. ... From the knowledge of the standard enthalpies of formation of reactants and products the standard enthalpy of reaction can be calculated using Hess’s law. ... For diatomic molecules like H2, O2, N2, HCl, HF etc
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Gurvinder Kaur 7 years, 11 months ago

From the pH we can calculate the hydrogen ion concentration. Knowing hydrogen ion concentration and the ionic product of water we can calculate the concentration of hydroxyl ions. Thus we have:
 [H+] = antilog (-pH)
= antilog [-9.95]
= 1.12 X 10-10
So, [OH-] = Kw  /  [H+]
= (1 X 10-14) / (8.91 X 10-5)
= 8.91 X 10-5 M
The concentration of the corresponding codenium ion is also the same as that of hydroxyl ion. Let the codeine ion be denoted by [M+]. Thus
Kb = [M+][OH-] / [MOH]
=  (8.91 X 10-5)2 / 0.005
= 1.59 X 10-6
pKb = -log Kb = - log(1.59 X 10-6)
pKb = 5.80

  • 4 answers

Pragati Singh 7 years, 11 months ago

Iss question ko 2 marks h , to Kya aap 2 marks ka answer de sakte h

Mohit Fdk 7 years, 11 months ago

Matlab me kuch smza ni fir se bolo

Pragati Singh 7 years, 11 months ago

Can u give this answer for 2 marks

Mohit Fdk 7 years, 11 months ago

Law of mass action, law stating that the rate of any chemical reaction is proportional to the product of the masses of the reacting substances, with each mass raised to a power equal to the coefficient that occurs in the chemical equation
  • 1 answers

Gurvinder Kaur 7 years, 11 months ago

Enthalpy of neutralization of is the heat change taking place when 1 gram equivalent of an acid (or base) is neutralized by 1 gram equivalent of base (or acid) in a dilute solution.
Heat of neutralization of strong acid-strong base is always constant, i.e. ΔH = -57.1 kj/mole.
HCl (aq) + NaOH (aq){tex}\to{/tex} NaCl (aq) + {tex}H_2O{/tex} (l)...ΔH = -57.1 kj/mole
Enthalpy of neutralization of any strong acid (like HCl, HNO3, H2SO4) with a strong base (like LiOH, NaOH, KOH) or vice versa is always the same i.e. 57.1 kj/mol. This is because strong acids, strong bases and salt that they form are all completely ionized in dilute aqueous solutions.
Thus the reaction between any strong acid and strong base for example in the above case may be written as :
NaOH (aq) + HCl(aq) {tex}\to{/tex} NaCl (aq) + {tex}H_2O{/tex} (l)... ΔH = -57.1 kj/mole
they will dissociate as :
Na(+) (aq) + OH(-) (aq) + H(+) (aq) + Cl(-) (aq) {tex}\to{/tex} Na(+) (aq) + Cl(-) (aq) + {tex}H_2O{/tex} (l)
common ions will cancel out..
H(+) (aq) + OH(-) (aq){tex}\to H_2O(l){/tex}
Therefore, neutralization is simply a reaction between H(+) ions given by acids and OH(-) ions given by base to form one mole of {tex}H_2O{/tex}.Since strong acid and strong base completely ionize in aqueous solution, the number of H(+) and OH(-) produced by 1 gram equivalent of strong acid and strong base is always the same, hence enthalpy of neutralization between a strong acid and strong base is always constant i.e. ΔH = -57.1 kj/mole.

  • 1 answers

Pragati Singh 7 years, 11 months ago

It is a white crystalline solid, contains units of tetrahedral shape , dissolve in water and form alkaline solution . Also called as tincal or sodium tetraborate
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Àñshul Shärmã 7 years, 11 months ago

Chlorine is formed at the anode
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Àñshul Shärmã 7 years, 11 months ago

Disproportionation is a chemical reaction typically a Redox reaction where a molecule is transformed into two or more dissimilar products
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Gurvinder Kaur 7 years, 11 months ago

Its a type of redox reaction in which a species reduced and oxidized simultaneously i.e. same element reduce and oxidise , to form two different products.
Example: Chlorine  gas reacts with dilute sodium<a href="https://en.wikipedia.org/wiki/Sodium_hydroxide" title="Sodium hydroxide"> </a>hydroxide to form sodium chloride, sodium chlorate and water. 
{tex}3 Cl_2 + 6 OH^− \to 5 Cl^− + ClO_3^ − + 3 H_2O{/tex}
The chlorine gas reactant is in oxidation state 0. In the products, the chlorine in the Cl ion has an oxidation number of −1, having been reduced, whereas the oxidation number of the chlorine in the ClO3  ion is +5, indicating that it has been oxidized.

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Biswajit Sahu 7 years, 11 months ago

Quantum
  • 0 answers

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