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Percent composition of C(carbon)=total mass of carbon in -C9H804 *100/ molar mass of C9H8O4 =12*9*100/12*9+1*8+16*4= 60% Percent composition of H (hydrogen)=total mass of hydrogen in C9H8O4*100/molar mass of C9H8O4 =8*100/180=4.5% Percent composition of O(oxygen)=mass of O in C9H8O4*100/ molar mass of C9H8O4 =16*4*100/180 =35.5%

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what is Boyle's law please ans me??

Posted by Vaishali ..... 5 years ago

CBSE > Class 11 > Chemistry

2 answers

Ankit ?? Kumar 5 years ago

P1v1=p2v2

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Yogita Ingle 5 years ago

Boyle’s Law

According to Boyle’s Law, the pressure (P) of a given mass of gas is inversely proportional to its volume (V), provided that the temperature of the gas remains constant.

For an enclosed gas, at constant temperature (T);
P ∝ 1/V

or, P × V = constant

ie; P₁V₁ =P₂V₂

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Define mole concept

Posted by Kritika Gupta 5 years ago

CBSE > Class 11 > Chemistry

2 answers

Yogita Ingle 5 years ago

The mole concept is a convenient method of expressing the amount of a substance. Any measurement can be broken down into two parts – the numerical magnitude and the units that the magnitude is expressed in. For example, when the mass of a ball is measured to be 2 kilograms, the magnitude is ‘2’ and the unit is ‘kilogram’.

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Mansi Vekariya 5 years ago

Mole Concept n = N/NA ...Molar mass of a Substance = (Mass of the Substance in grams)/(Number of Moles) ...Number of Moles = (Mass of the Sample)/(Molar Mass) ...Number of Atoms or Molecules = (Number of Moles)*(6.022*1023) ...1 amu = (1gram)/(6.022*1023) = 1.66*10-24 grams.

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Define dalton atomic theory

Posted by Kritika Gupta 5 years ago

CBSE > Class 11 > Chemistry

1 answers

Yogita Ingle 5 years ago

Dalton’s atomic theory was a scientific theory on the nature of matter put forward by the English physicist and chemist John Dalton in the year 1808. It stated that all matter was made up of small, indivisible particles known as ‘atoms’. The postulates and limitations of Dalton’s atomic theory are listed below.

Postulates of Dalton’s Atomic Theory

All matter is made up of tiny, indivisible particles called atoms.
All atoms of a specific element are identical in mass, size, and other properties. However, atoms of different element exhibit different properties and vary in mass and size.
Atoms can neither be created nor destroyed. Furthermore, atoms cannot be divided into smaller particles.
Atoms of different elements can combine with each other in fixed whole-number ratios in order to form compounds.
Atoms can be rearranged, combined, or separated in chemical reactions.

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The percentage of carbon is Ca(HCO3)2 IS

Posted by Gaurav Moran 5 years ago

CBSE > Class 11 > Chemistry

1 answers

Mamali Mishra 5 years ago

As we know, mass percent of an element= mass of the element/ molar mass of the compound given In Ca(HCO3)2, the mass of carbon is 24g and the molar mass of the compd. is 162g. Mass % of C = 24/162× 100= 400/27%

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When electron jumps form 5 th energy level to 4 th energy level the spectral line emitted is found in which region

Posted by Vaishali M 5 years ago

CBSE > Class 11 > Chemistry

2 answers

Ankit ?? Kumar 5 years ago

Infra red region

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Pk . 5 years ago

Short infra-red region

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State Avogardro's law

Posted by Yachna Solanki 5 years ago

CBSE > Class 11 > Chemistry

2 answers

Mamali Mishra 5 years ago

It states that V(volume) is directly proportional to the no. of atoms

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Kritika Gupta 5 years ago

Equal volume of all gases under similar condition of temperature and pressure contain equal number of atoms

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How to molarity calculate

Posted by Raj Yadav 5 years ago

CBSE > Class 11 > Chemistry

2 answers

Yogita Ingle 5 years ago

The equation for calculating molarity is the ratio of the moles of solute whose molarity is to be calculated and the volume of solvent used to dissolve the given solute.

M = n/V

Here,

M is the molality of the solution that is to be calculated

n is the number of moles of the solute

V is the volume of solution given in terms of litres

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Priyanshu Bhatt 5 years ago

I don't know

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How ionisation enthalpy varies in the period

Posted by Ayush Bansal 5 years ago

CBSE > Class 11 > Chemistry

1 answers

Yogita Ingle 5 years ago

Ionization enthalpy decreases down the group on moving from top to bottom in a periodic table.

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Scientist notation meaning

Posted by Raj Solanki 5 years ago

CBSE > Class 11 > Chemistry

1 answers

Rewat Singh Shekhawat 5 years ago

Scientific notation is a way of expressing real numbers that are too large or too small to be conveniently written in decimal form.

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Yes seriously

Posted by Lavish Kumar 5 years ago

CBSE > Class 11 > Chemistry

3 answers

Annu Yadav 5 years ago

Kaha ho tum

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Aarohi Singh 5 years ago

Gaurav Seth you have copied the 10 th class English chapter summary

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Gaurav Seth 5 years ago

Anil does not hand over the thief to the police because he realized that Hari had learnt his lesson and had changed for the better. Otherwise, he would never have come back and kept the money at the same place from where he had stolen it. Anil even knew how Hari cheated him of a rupee a day while buying the day’s supplies. But he never said anything to him. This is such a case where most people would have handed him over to the police. Anil was different from such employers because he was a modest and trusting man. He had offered to teach Hari how to cook and also to educate him. When he found out that Hari had stolen the money, but had kept it back, he knew that it was Hari’s conscience that had made him do so. Hari could have easily run off with the money, but he did not. This made Anil give him another chance and build him into a better person that he could already see him becoming.

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Hey guys back to school from 1 September ???

Posted by Lavish Kumar 5 years ago

CBSE > Class 11 > Chemistry

5 answers

Annu Yadav 5 years ago

Seriously

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Lavish Kumar 5 years ago

Okay Sona

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Dark ..? 5 years ago

internet...... is always not true ....

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Lavish Kumar 5 years ago

But I saw on internet that schools from 9 to 12 are going to be reopen on 1 September

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Dark ..? 5 years ago

this is not true..

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What is mol of 5.6 litres of O2 at STP?

Posted by Varsha Meena 5 years ago

CBSE > Class 11 > Chemistry

1 answers

Gaurav Seth 5 years ago

First and foremost, keeping in mind that at room temperature, Oxygen is a gas.

So, Volume of Oxygen(O2) given = 5.6L.

Finding moles, Moles=Volume/22.4.

Moles= 5.6/22.4=1/4moles.

So, finding mass of O2= moles × Mol. Wt.

Mass( in grams) = 1/4 × 32. We have taken 32 as oxygen is is combined state O2, so 16×2=32.

We get, mass =8 grams.

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What is mol of 6.022×10^23 molecules of H2O

Posted by Varsha Meena 5 years ago

CBSE > Class 11 > Chemistry

1 answers

Ankit ?? Kumar 5 years ago

1 mol

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What is SI unit of mole fraction?

Posted by Varsha Meena 5 years ago

CBSE > Class 11 > Chemistry

1 answers

Yachna Solanki 5 years ago

NO unit ,Because it is a ratio , mole fraction is a unitless expression . The mole fraction of all components of a solution, when added together , will equal 1

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2 moles of A and 3moles of B react to form AB. A+B---- AB. What is the limiting reagent

Posted by Ashi Isha 5 years ago

CBSE > Class 11 > Chemistry

0 answers

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What is flux and its types

Posted by Tanishq Yadav 5 years ago

CBSE > Class 11 > Chemistry

1 answers

Meghna Thapar 5 years ago

Flux:

It is the substance added to molten metals to bond with impurities that can be readily removed.

Types of flux:

Fluxes are of two types, viz, acidic flux and basic flux.

(a) Acidic flux: It is an acidic oxide (oxide of a non-metal) like SiO₂, P₂O₅, B₂O₃ (from borax). It is used to remove basic impurities like CaO, FeO, MgO etc. The acidic flux combines with a basic impurity to form a slag.

(b) Basic flux: It is a basic oxide (i.e. oxide of a metal) like CaO (obtained from limestone, CaCO₃), MgO (from magnesite. MgCO₃), haematite (Fe₂O₃) etc. It is used to remove acidic impurities like SiO₂, P₂O₅ etc. The basic flux combines with an acidic impurity to form a slag.

Thus, slag can be defined as a fusible mass, which is obtained when a flux reacts with an infusible, acidic or basic impurity present in the oxide ore.

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What is g-equivalent

Posted by Lavish Kumar 5 years ago

CBSE > Class 11 > Chemistry

2 answers

Lavish Kumar 5 years ago

Ok Annu ??❤️❤️

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Annu Yadav 5 years ago

Google pe sarch kar lo

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What are limiting reagents

Posted by Lavish Kumar 5 years ago

CBSE > Class 11 > Chemistry

2 answers

Lavish Kumar 5 years ago

Thank you so much for the definition bcoz I was eagerly searching for that ????

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Yogita Ingle 5 years ago

Limiting reagents are the substances that are completely consumed in the completion of a chemical reaction. They are also referred to as limiting agents or limiting reactants. According to the stoichiometry of chemical reactions, a fixed amount of reactants is required for the completion of the reaction. Let us consider the following reaction of formation of ammonia:

3H₂ + N₂ → 2NH₃

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SI unit of density

Posted by Alir Engtipi 5 years ago

CBSE > Class 11 > Chemistry

3 answers

Lavish Kumar 5 years ago

Kg per meter cube

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Abhay Jeet 5 years ago

3 Kg/m

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Jasmeen Kaur 5 years ago

SI unit of density is kg/m3. ?

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What is Heisenberg uncertainty

Posted by Alir Engtipi 5 years ago

CBSE > Class 11 > Chemistry

1 answers

Yogita Ingle 5 years ago

According to Heisenberg ,it is impossible to measure both the position and momentum of moving particle with accuracy.

If value of position is small ,it can be measured accurately but not momentum.
If value of momentum is small it is measured accurately but not the position.

Mathematically that means:
ΔxΔp > h/2 π

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Define law of conservation of mass

Posted by Monjir Terangpi 5 years ago

CBSE > Class 11 > Chemistry

2 answers

Aniket Yadav 5 years ago

According to the law of conservation of mass matter cen neither be created nor destroyed

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Jasmeen Kaur 5 years ago

Acc. to this law, mass can neither be created or nor destroyed in a chemical reaction. The total mass in reactant side must be equal to the total mass in product side.

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Convert 450 pm into SI unit and write the answer in scientific notation upto 2 significant figures.

Posted by Bhagyasree Panda 5 years ago

CBSE > Class 11 > Chemistry

3 answers

Bhagyasree Panda 5 years ago

Please sir

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Bhagyasree Panda 5 years ago

Sir please give me full solution

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Karan Kannake 5 years ago

4.5 *10^2 this is the answer

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In an organic compound mass% of carbon, hydrogen, nitrogen is 40.57%, 8.53% , 23.65%, respectively, the rest is oxygen. The molar mass of compound is 59. What is its molecular formula.

Posted by Shivika Choudhry 5 years ago

CBSE > Class 11 > Chemistry

1 answers

Anamika Bharti 5 years ago

C2H5NO

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Calculate the wave number corresponding of the following wave length 1 3000

Posted by Lokesh M 11B39 5 years ago

CBSE > Class 11 > Chemistry

1 answers

Lavish Kumar 5 years ago

Ufuf

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What is the oxidation number of Mn in Mno-4 and C in CH2CL2

Posted by Aniket Bhaskar 5 years ago

CBSE > Class 11 > Chemistry

1 answers

Megha Agarwal 5 years ago

Mn is 8 and C is 0

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How many moles of caco3 are present in 10gm of substance(ca=40,c=12,o=16)

Posted by Harsh Jha 5 years ago

CBSE > Class 11 > Chemistry

3 answers

Ashi Isha 5 years ago

0.1 mole

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Harman Singh 5 years ago

W= 10gm Molar mass= 100u No. of moles = 10/100 =0.1 mol

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Shiva Rajput 5 years ago

0.1mol

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Explain why all d block elements are more transparent elements

Posted by Sarla Yadav 5 years ago

CBSE > Class 11 > Chemistry

0 answers

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which has higher energy a photon of red light with wavelength 7500 angsron or a photon of green light with wavelength of 5250angsron

Posted by Agent Wolf 5 years ago

CBSE > Class 11 > Chemistry

1 answers

Agent Wolf 5 years ago

Wavelength of red light (λ) = 7500 A∘ = 7500×10−10 m As we know : Energy of light = hcλ where h (planck's constant) = 6.626×10−34Jsand c (speed of light) = 3×108m/s ∴ Energy = 6.626×10−34Js ×3×108m/s7500×10−10m = 2.6504 × 10−19J and for green light wavelength (λ) = 5250 A∘ = 5250×10−10 m ∴ Energy = 6.626×10−34Js ×3×108m/s5250×10−10m = 3.7863 × 10−19J Thus red light with greater wavelength has lower energy than green light.

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