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  • 1 answers

Sia ? 4 years, 2 months ago

To describe the structure of atom and laws of chemical combination, Dalton’s Atomic Theory was put forward. According to this theory, matter is made up of small particles called atoms which are indivisible and indestructible. Atoms of same element are identical in shape, size, mass and chemical properties but the properties are different for atoms of different elements. They react with each other in different ratios (in simple whole number ratios) to form compounds or molecules.

This theory has some limitations like

1) It can explain the laws of chemical combination by mass but not by gaseous volumes.

2) it cannot explain why atoms of different elements have different properties.

3) Why atoms of different elements combine to form molecules?

4) What is the nature of binding forces that exist between atoms and molecules to form three states i.e. solid, liquid and gases?

To explain all above points modern atomic theory was introduced. According to this theory-

1) Atom is not indivisible as it is not the smallest particle. It is made up of electrons, protons and neutrons.

2) Atoms of different elements may have same atomic masses. Such atoms are called isobars.

3) Atoms of same element may have different atomic number. These atoms are called isotopes.

4) Atoms of different elements may react with each other in integral ratios also. It is not necessary to react in simple whole number ratios to form compounds or molecules.

5) Atoms are not indestructible. Atom of one element can be changed into another.

Because of all these explanations that modern atomic theory can give, it is better than Dalton's Atomic theory.

  • 3 answers

Adithya Dev A 4 years, 2 months ago

It is the "clouded" area around a nucleus where there is most probability of finding an electron. It is based on Heisenberg's Uncertainty principle.

Ankita Singh 4 years, 2 months ago

Electron arrange themselves in cloudlike region around the nucleus called orbital

Aryan Dhaka 4 years, 2 months ago

Orbital means pagal hai kya
  • 1 answers

Sia ? 4 years, 2 months ago

ψ is a wave function and refers to the amplitude of electron wave i.e. probability amplitude. It has got no physical significance. The wave function ψ may be positive, negative or imaginary.
[ψ]2 is known as probability density and determines the probability of finding an electron at a point within the atom. This means that if:
(i) is zero, the probability of finding an electron at that point is negligible.
(ii) [ψ]2 is high, the probability of finding an electron is high i.e. electron is present at that place for a long time.
(iii) [ψ]2 is low. the probability of finding an electron is low i.e. electron is present at that place for a shorter time.

  • 1 answers

Sia ? 4 years, 2 months ago

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  • 1 answers

Priyanshi Sharma 4 years, 2 months ago

Yes, the reduced syllabus will also come in the neet exam as it is an entrance exam.
  • 1 answers

K I L L E R . 4 years, 2 months ago

The magnetic quantum number of an electron is one of the four quantum numbers that state the position of the electron with respect to the nucleus. The other three are- Principal quantum number Azimuthal quantum number Spin quantum number
  • 1 answers

Adithya Dev A 4 years, 2 months ago

1 mole is the amount of substance which has a mass equal to 1 g ie, the mass of 6.022 * 10^ 23 elementary entities. In a gas, 1 mole volume is equal to 22.4 l.
  • 1 answers

Adithya Dev A 4 years, 2 months ago

W2 = ?, M2 = 12 + 3 + 12 + 16 + 16 + 23 = 27 + 55 = 82g. V = 500 mL. M = 0.375 mol/L. Therefore, M = W2 /M2V * 1000. W2 = MM2V / 1000 = 0.375 * 82 * 500/1000 = 0.375 * 41 = 15.375g.
  • 2 answers

Sia ? 4 years, 2 months ago

let vitamin C empirical formula is CxHy
CxHy + (x +y/4) O2 ------> xCO2 + y/2 H2O
now,
you see 1 mole of vitamin C form x mole CO2 and y/2 mole of H2O
so,
(0.2000)/(12x+y)= x (0.2998)/(44)
again,
(0.2000)/(12x + y)= y/2 (0.819)/(18)
divide both,
1 = x (0.2998). (18)/y/2 (0.819)(44)
y (0.819)(22) = x (0.2998)(18)
x/y = (0.2998)(18)/(0.819)(22)
= 3/10
hence, empirical formula of vitamin C is C3H10

Gurkirt Singh 4 years, 2 months ago

Hello
  • 2 answers

Aman Kumar 4 years, 2 months ago

2*10^-6m^3

Aman Kumar 4 years, 2 months ago

2*10^-6m^3
  • 1 answers

Adithya Dev A 4 years, 2 months ago

Molar mass of H2SO4 = 98 g. Therefore, M = 9.8/(98 * 100) * 1000 = 1 M.//
  • 1 answers

??? ??? 4 years, 2 months ago

Molar mass of argon= Atomic mass of 36 Ar = 35.96755 and abundance = 0.337 Total atomic mass of 40 Ar = 39.9624*99.600= 39.802g/mol Therefore molar mass of argon = total mass of 36 Ar + total mass of 38 Ar + atomic mass of 40 Ar= 0.121+0.024+39.802 = 39.947g/ mol.
  • 1 answers

??? ??? 4 years, 2 months ago

2s orbital have larger effective nuclear charge than 3s orbital because 2s is closer than 3s to the nucleus.
  • 2 answers

Preeti Dabral 4 years, 2 months ago

molar mass of CO2=44g
molar mass of NO =15g
no of molecules in 15 g NO= NA
no of molecules in 3g of NO=(3/15)NA
given, molecules in 3g of NO=molecules in m g of CO2
m/44×NA=3/15×NA
m=3×44/15
=8.8g of CO2

Samy Banik 4 years, 2 months ago

wow
  • 1 answers

Preeti Dabral 4 years, 2 months ago

Classical mechanics fails when applied to microscopic objects like electrons, atoms and molecules, etc. This is because the classical mechanics ignores the concept of dual nature of matter. The branch of science that takes into account this dual behaviour of matter is called quantum mechanics.The absorption and emission spectra of hydrogen like atom explained by Bohr theory is the experimental evidence in support of the idea that electronic energies in an atom are quantized. The various line obtained in the spectrum of hydrogen (Lyman,. Balmar, Paschan , Brackett and Pfund series) are based on the assumption of electronic energies in an atom are quantized.

  • 2 answers

Prajwal Pandey 4 years, 2 months ago

4

Adithya Dev A 4 years, 2 months ago

4.
  • 1 answers

Preeti Dabral 4 years, 2 months ago

Rubidium is the chemical element with the symbol Rb and atomic number 37.

  • 1 answers

Rahul Nadagoud 4 years, 2 months ago

Molar mass of NH3=17 gm In 17gm of NH3=3gm of hydrogen In 85gm ofNH3=? 85×3÷17=15 gm
  • 1 answers

Anurag Singh 4 years, 2 months ago

CuSo4---- calculate over all mas 4H2O------ calculate over all mas Divide 1 element mass present in compound by over all mass of compound and then multiply by 100 to get percentage
  • 1 answers

Khushi Yadav 4 years, 2 months ago

Wave number= 1.72×10^6m^-1 Frequency= 1.5172×10^14s^-1
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Rahul Nadagoud 4 years, 2 months ago

C=12×6=72u H=12u,. O=16×6=96u Total molecular mass=72+12+96=180u

Khushi Yadav 4 years, 2 months ago

180u

Ishita Rana 4 years, 2 months ago

180.56
  • 1 answers

Nidhi Kashyap?? 4 years, 3 months ago

Mass can neither be created nor be destroyed
  • 1 answers

Khushi Yadav 4 years, 2 months ago

Charge of electron= 1.6×10^-19×6.022×10^23 = 9.6352×10^4 Mass of electron= 9.1×10^-31×6.022×10^23 = 5.48008×10^-7

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