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  • 2 answers

Kamlesh Kks 5 years, 9 months ago

Acid rain,industial wastes,some domestic work of human and due to leaves,grass,trash etc.

Devil ? 5 years, 9 months ago

Dumping industrial waste into rivers without proper treatment.. Use of chemical detergents
  • 1 answers

Abhi Singh 5 years, 9 months ago

In order to determine the hybridization of sulfur tetrafluoride, you have to first understand its Lewis structure and the number of valence electrons that are present. The SF4 molecule consists of a total of 34 valence electrons. Here 6 will come from sulfur and each of the four fluorine atoms will have 7 electrons.
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Abhi Singh 5 years, 9 months ago

In kO2 oxidation state of each oxygen is -1/2. let oxidation state of k in KO2 be x x+2(-1/2)=0 x=+1 hence, oxidation state of k is +1
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Devil ? 5 years, 9 months ago

Electrons are filled acc to their energy by using hunds pauli afbhau principle ...
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Devil ? 5 years, 9 months ago

Hard water contain calcium and magnesium choride and sulphate Soft water only contain calcium and magnesium hydroxide

Abhi Singh 5 years, 9 months ago

Hard water... is water that contains an appreciable quantity of dissolved minerals (like calcium and magnesium). Soft water... is treated water in which the only ion is sodium.
  • 1 answers

Mubarak Hussain 5 years, 9 months ago

*what
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Yogita Ingle 5 years, 9 months ago

Salts can be classified into the following types:

a) Normal salt

A salt that does not contain any replaceable hydrogen ions is a normal salt. It is obtained by replacing all the hydrogen ions of an acid by metal ions or ammonium ions. Examples: NaCl, Na2SO4, Na3PO4, NH4Cl, K2CO3, CuSO4 etc.

b) Bisalts or Acid salts

A bisalt, or an acid salt contains replaceable hydrogen ions in association with the acidic radicals. It is obtained by the incomplete replacement of hydrogen ions by metal ions or ammonium ions.

Examples: NaHCO3, NaH2PO4 and Na2HPO4.

Since such salts also contain hydrogen ion, the term 'bi' or acid can be substituted by hydrogen, e.g. sodium bicarbonate or sodium acid carbonate is also called sodium hydrogen carbonate.

When bisalts or acid salts dissociate in water, they yield hydrogen or hydronium ions.

  • 1 answers

Gurmandeep Singh 5 years, 9 months ago

Rutherford model,Bohr model,Rutherford scattering experiment, Aufbau principl,difference between atomic & emission spectra. Numerical of molality, molarity, normality.
  • 1 answers

Manisha Tiwari 5 years, 9 months ago

As gibbs free energy is equal to Enthalapy - temperature multiplied by entropy therefore if we increase the temperature value of gibbs free energy decreases or becomes negative or in simpler terms the reactions move towards spontaneity
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Yogita Ingle 5 years, 9 months ago

Quantum numbers: Quantum numbers are numbers that designate and distinguish various atomic orbitals and electrons present in an atom.
Four quantum numbers are used to define the state of an electron completely, namely principal quantum number, azimuthal quantum number, magnetic quantum number and spin quantum number.

Principal quantum number:
Principal quantum number determines the energy shell in which an electron revolves around the nucleus.
Principal quantum number is also known as the major energy level.
Principal quantum number is denoted by the symbol n.
Principal Quantum Number (n) = 1, 2, 3, …….
 

  • 1 answers

Mr. Badmash 5 years, 9 months ago

Dipole moment of NH3 is more than NF3
  • 1 answers

Gaurav Seth 5 years, 9 months ago

Preparation :
When we heat baking soda then hydrogen gas released and sodium carbonate left.
When water is added to sodium carbonate then it becomes washing soda.
Equation :
2Nahco3 = Na2CO3 +h2O+co2
Na2CO3 +10h2O =Na2CO3.10H2O

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Yogita Ingle 5 years, 9 months ago

Generally, the electronic configuration of these elements is (n-1) d 1–10ns 1–2. The (n–1) remains for the inward d orbitals which may have one to ten electrons and the peripheral ns orbital may have one or two electrons. The d–block involves the middle area flanked by s– and p– blocks in the periodic table. The very name "transition" given to the elements of d-block is simply because of their position amongst s– and p– block elements. The d–orbitals of the penultimate energy level in their atoms get electrons leading to the three columns of the transition metals, i.e., 3d, 4d and 5d. The fourth line of 6d is still inadequate

  • 2 answers

Aryan Borasi 5 years, 9 months ago

In atomic physics and quantum chemistry, the electron configuration is the distribution of electrons of an atom or molecule in atomic or molecular orbitals. For example, the electron configuration of the neon atom is 1s² 2s² 2p⁶, using the notation explained below.

Gaurav Seth 5 years, 9 months ago

Electronic configuration is defined as the distribution of electrons into various orbitals of an atom by using three principles.

Aufbau principle states that in the ground state of the atoms the orbitals are filled in order of their increasing energies. Electrons first occupy the lowest-energy orbital and then enter into successive higher energy orbitals. The electrons enter into various orbitals in an increasing order of (n+l).

Pauli's Exclusion Principle states that: An orbital can have maximum two electrons with opposite spin.

Hund's Rule of Maximum Multiplicity states that: Electron pairing in p, d and f orbitals cannot occur until each orbital of a given sub-shell contains one electron each or is singly occupied.

  • We can represent the electronic configuration of atoms in two ways.
  • Orbital diagram method
  • nlx method


Electronic configuration of the first ten elements - Hydrogen, Helium, Lithium, Beryllium, Boron, Carbon, Nitrogen, Oxygen, Fluorine, and Neon given in following table.

After filling the 2p orbitals, the electrons fill into the 3s and then the 3p orbitals.

The electronic configurations of most of the elements can be write in a simplified manner or condensed form.

The eleventh electron in Sodium will enter the 3s orbital. Therefore, the electronic configuration of Sodium can also be written in a condensed form as [Ne] 3s¹.

Following table gives condensed form for elements from Sodium to Potassium.

  • 2 answers

Muskaan ? 5 years, 9 months ago

Bond lngth longer

Muskaan ? 5 years, 9 months ago

Cyclic resonance
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  • 1 answers

Sunita Kumari 5 years, 9 months ago

Orbit -1 It is a well defined circular path where the electrons revolve 2 It represents the planar motion of electrons around the nucleus 3 The number of electrons present is 2nsquare electrons Orbital -1 It is a 3-D region
  • 1 answers

Mohit Panchal 4 years, 6 months ago

State the main advantage of molality over molarity as the unit of concentration
  • 3 answers

Tanvi Sharma 5 years, 9 months ago

What does it mean to say????

Ashish Bhardwaj 5 years, 9 months ago

Hloo

Tanvi Sharma 5 years, 9 months ago

Take unknown elements oxidation no as x and solve the problem
  • 1 answers

Pratik Dahal 5 years, 9 months ago

Let take a question 2C + 2O2-->2CO2 here , 2 is the stoichiometric coefficient of C,O2,CO2

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