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What is the difference between electro magnetic waves and matter waves

Posted by Deepak Bhatt 6 years, 6 months ago

1 answers

Yogita Ingle 6 years, 6 months ago

S.No.	Electromagnetic Waves	Matter Waves
1	Associated with electrical and magnetic fields.	Not associated with electrical and magnetic fields.
2	Can be emitted or radiated in space.	Neither radiated into space nor emitted by the particles. These are simply associated with the particles.
3	Travel with the same velocity.	Travel with different velocities.
4	Velocity is equal to that of the velocity of light i.e. 3 x 10 8 ms-1.	Velocity is different from that of light.
5	The wavelength is given by lambda = c/v = h/mc.	The wavelength is given by lambda = h/mw = h/p.

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What hydorgen

Posted by Harsh Dewangan 6 years, 6 months ago

CBSE > Class 11 > Chemistry

5 answers

@ Maurya 6 years, 6 months ago

Element persent in s block

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Ravi Nathera 6 years, 6 months ago

Element

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Vishal Yadav 6 years, 6 months ago

1st member of sblock

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Farhat Shaikh Shaikh 6 years, 6 months ago

Eliment

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Shraddha Tiwari 6 years, 6 months ago

It's an element

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ideal gas equation derivation

Posted by Sahil Sharma 6 years, 6 months ago

CBSE > Class 11 > Chemistry

1 answers

Satyam Krishna 6 years, 6 months ago

pv =nrt

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Number of angular nodes for 4d orbitals is?

Posted by Niraj Kushwaha 6 years, 6 months ago

CBSE > Class 11 > Chemistry

2 answers

Sia ? 6 years, 6 months ago

two

There are four nodes total (5-1=4) and there are two angular nodes (d orbital has a quantum number(ℓ = 2) on the xz and zy planes.

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Esha Pal 6 years, 6 months ago

It will be 3

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Is threshold frequency same as minimum frequency???

Posted by Preeti Rahi 6 years, 6 months ago

CBSE > Class 11 > Chemistry

1 answers

Sia ? 6 years, 6 months ago

Threshold frequency is defined as the minimum frequency of light which causes electrons to be emitted from a metal surface

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Calculate the energy associated with the first orbit of He+. What is the radius of This orbit ?

Posted by Jigna Chingakham 6 years, 6 months ago

CBSE > Class 11 > Chemistry

1 answers

Krishna Priya 6 years, 6 months ago

E=-2^2/1^2×E○ = -4E○ =-4×13.6=-54.4 R=1^2/2×r○ =1/2×0.529×10^-10m =2.645×10^-11 m

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calculate the mass of a photon with wavelength 3.6 angstrong

Posted by Jigna Chingakham 6 years, 6 months ago

CBSE > Class 11 > Chemistry

0 answers

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2 ton of iron ore containing 94% of fe2o3 produce iron in pure state calculate the weight of iron?

Posted by Arpit Verma 6 years, 6 months ago

CBSE > Class 11 > Chemistry

2 answers

Arpit Verma 6 years, 6 months ago

But it cant given that 160kg of iron oxide has 112kg of iron than by what ways you solve this question???

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Gaurav Seth 6 years, 6 months ago

Mass of iron oxide present = 940x 2 = 1880 kg
160 kg of iron oxide has 112 kg of iron
hence 1880 kg will have 112/ 160 x 1880 = 1316 kg of iron
hence mass of iron produced is 1316 kg

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ANSWER

What is the difference betwn molarity and molality ?

Posted by Ravi Kant 6 years, 6 months ago

CBSE > Class 11 > Chemistry

1 answers

Sia ? 6 years, 6 months ago

Molality (m) : It is the number of moles of the solute dissolved per kilogram (kg) of the solvent. It is denoted by m.
{tex}\therefore{/tex} Molality (m) {tex} = \frac{{{\text{No}}{\text{. of Moles of solute}}}}{{{\text{Mass of solvent in kg}}}}{/tex}
{tex}\therefore \,m = \frac{{{W_2} \times 1000}}{{{M_2} \times {W_1}}}{/tex}
Where W₁= mass of solvent
W₂ = mass of solute
M₂ = Molar mass of solute . Unit is mol/Kg
Molarity (m): It is the number of moles of the solute dissolved per litre of the solution. It is denoted by M.
Molarity {tex} = \frac{{{\text{No}}{\text{. of moles of solute}}}}{{{\text{Volume of solution in litre}}}}{/tex}
{tex}\therefore \;M = \frac{{{W_2} \times 1000}}{{{M_2} \times {V_1}}}{/tex}
where W₂ = mass of solvent
M₂ = molar mass of solute
V = Volume of solution. Unit is mol/L
The molarity and molality of a solution will be nearly same if the mass of solvent is nearly equal to the volume of solution.

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What is the difference between precision and accuracy ?

Posted by Ravi Kant 6 years, 6 months ago

CBSE > Class 11 > Chemistry

2 answers

Sia ? 6 years, 6 months ago

Precision means the closeness of various measurements for the same quantity. For example, if in a lab you weigh a given substance five times, and you get same result each time, then your measurement is very precise. Actually, Precision is independent of accuracy.

On the other hand, Accuracy is the agreement of a particular value to the true value of the result. For example, if in a lab you obtain a weight measurement of 4.5g for a given substance, but the actual weight is 9 g , then your measurement is not accurate. Because , in this case your measurement is not close to the know value.

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Preeti Rahi 6 years, 6 months ago

Refer to ncert. Perfect explanation is given there

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Statement of Low of Multiple Proportion.

Posted by Alok Singh 6 years, 6 months ago

CBSE > Class 11 > Chemistry

2 answers

Sia ? 6 years, 6 months ago

Law of multiple proportions states that when two elements combine with each other to form more than one compound, the weights of one element that combine with a fixed weight of the other are in a ratio of small whole numbers.

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Alok Singh 6 years, 4 months ago

What is Avogadro's number 0?

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When 2.86 g of mixture of 1 butene c4h8 and butane c4h10 was burned in excess of oxygen 8.80 g of co2 and 4.14 g of h20 were obtained what is the percentage by mass of butane in the mixture

Posted by Manav Bansal 6 years, 6 months ago

CBSE > Class 11 > Chemistry

0 answers

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Define mole and 1mole of a substance

Posted by Dr.Chemlut Siangshai 6 years, 6 months ago

CBSE > Class 11 > Chemistry

1 answers

Angel Subba 6 years, 6 months ago

Mole is the metric (SI) unit of amount (not mass or weight) of a substance. One mole is defined as the amount of substance containing as many elementary entities (atoms,molecules,ions,etc.)

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Calculate mass of photon of sodium light having wavelength 1.894 A and velocity 3×10^8

Posted by Harman Deep 6 years, 6 months ago

CBSE > Class 11 > Chemistry

0 answers

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Why is phosphorus acid (H3PO3) di asic ?

Posted by Esha Dutt 6 years, 6 months ago

CBSE > Class 11 > Chemistry

1 answers

Yogita Ingle 6 years, 6 months ago

H₃PO₃ has three hydrogen atoms and looking at the structure it is clear that in H₃PO₃ only two hydrogen atoms are joined through the oxygen atoms and are ionisable. The third hydrogen atom is linked to P-atom directly and is not ionisable. The H-atom joined to the P- atom is reducing in nature and is not ionisable as a proton and therefore H₃PO₃ acts as a dibasic acid.

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how can we write 0.00016 in scientific notation

Posted by Raviprasath S 6 years, 6 months ago

CBSE > Class 11 > Chemistry

3 answers

Devil ? 6 years, 6 months ago

1.6 *10^-4

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Aksh Panchal 6 years, 6 months ago

16 into 10 to the power minus 5

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Raviprasath S 6 years, 6 months ago

1.6*104

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What's the volume of hcl

Posted by Dip Debnath 6 years, 6 months ago

CBSE > Class 11 > Chemistry

0 answers

ANSWER

27g of al will react completely with how mamy grams of oxygen

Posted by Sonal Soroy Soroy 6 years, 6 months ago

CBSE > Class 11 > Chemistry

1 answers

Sia ? 6 years, 6 months ago

24 g

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Show the decomposition of Caco3 follow law of conservation of mass

Posted by Trisha Srivastava 6 years, 6 months ago

CBSE > Class 11 > Chemistry

1 answers

Navratna Solanki 6 years, 6 months ago

CaCO3-----CaO+CO2

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Maxwell model of atom

Posted by Saurav Kumar 6 years, 6 months ago

CBSE > Class 11 > Chemistry

1 answers

Saurav Kumar 6 years, 6 months ago

Maxwell model of atoms

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Sir i need important questions for class 11 2019

Posted by Indian Status 6 years, 6 months ago

CBSE > Class 11 > Chemistry

0 answers

ANSWER

Explain Azimuthal laws?

Posted by Manish Sahu 6 years, 6 months ago

CBSE > Class 11 > Chemistry

1 answers

Sia ? 6 years, 6 months ago

The azimuthal quantum number, ℓ, is the quantum number associated with the angular momentum of an atomic electron.

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The atomic weight of cu is 63.54.There are only two naturally ocurring isotopes of copper 63cu and 63cu. There natural abundance of the 63cl isotope must be approximately. a.10%. b.30% c.50%. d.70%

Posted by Kuki Reddi 6 years, 7 months ago

CBSE > Class 11 > Chemistry

0 answers

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1.6g of a hydrogen on complete combustion gave 4.4g of CO2 and 3.6g of H2O show that this data proves law of conservation of mass

Posted by Aditya Dohare 6 years, 7 months ago

CBSE > Class 11 > Chemistry

0 answers

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An average cup of coffee contains about 125 mg of caffeine, C 8 H 10 N 4 O 2 . How many moles of caffeine are in a cup, and how many molecules of caffeine?

Posted by Arya Jha? 6 years, 7 months ago

CBSE > Class 11 > Chemistry

0 answers

ANSWER

Mole of electrons present in 9g aluminium is

Posted by Amira Verma 6 years, 7 months ago

CBSE > Class 11 > Chemistry

4 answers

Sia ? 6 years, 7 months ago

Number of moles of 9 g of Al³⁺ ion = {tex}\frac{9}{27}{/tex}(given mass/molar mass)

Now, number of ions of Al³⁺ = {tex}\frac 13 \times 6.022 \times 10^{23}{/tex}= 2.007 {tex}\times{/tex} 10²³(number of ions/atoms/molecules=Avogadro's number*number of moles)

Now, number of electrons in 1 ion of Al³⁺ = 10

So, 2.007 {tex}\times{/tex} 10²³ ions will have 2.007 {tex}\times{/tex} 10²³ {tex}\times{/tex} 10 = 2.007 {tex}\times{/tex} 10²⁴ electrons.

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Amira Verma 6 years, 6 months ago

Hi Esha Pal

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Esha Pal 6 years, 7 months ago

Hlo amira

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Amira Verma 6 years, 7 months ago

Its ans is 4.33 but i donot know how

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how to make achart on ostwald process?

Posted by Rohit Singh Sheoran 6 years, 7 months ago

CBSE > Class 11 > Chemistry

1 answers

Sia ? 6 years, 7 months ago

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A compound contains 4.07% hydrogen, 24.27% carbon and 71.65% chlorine. Its molar mass is 98.96gram .What are the empirical formula and molecular formula

Posted by Abhishek Raj 6 years, 7 months ago

CBSE > Class 11 > Chemistry

2 answers

Tanvi Chauhan?? 6 years, 7 months ago

First convert mass percent to grams 4.07%- 4.07g 24.27%-24.27g 71.65%-71.65g Then find no. Of moles of each element M of Hydrogen=4.07/1.008=4.04 M of carbon =2.021 M of chlorine=2.021 Divide each of the mole values obtained above by the smallest no. Among them Ratio:2:1:1 forH:C:Cl Empirical formula-CH²Cl Now molecular formula Empirical formula mass : 12.01+(2*1.008)+35.453=49.98g

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Tanvi Chauhan?? 6 years, 7 months ago

This is an example of ncert book

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Atomic mass unit,formula mass Calculation and molecular mass book back questions

Posted by Vinith Vinith 6 years, 7 months ago

CBSE > Class 11 > Chemistry