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Ask QuestionPosted by Royal Thakur ? 3 years, 11 months ago
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Yogita Ingle 3 years, 11 months ago
Molar mass (M) is the mass of 1 mole of a chemical substance. The unit for molar mass is grams per mole or g.mol−1-1.
Posted by ?Ritesh Gupta? 3 years, 11 months ago
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Anmol Agarwal 3 years, 11 months ago
Gaurav Seth 3 years, 11 months ago
Mole Concept
Term mole was suggested by Ostwald (Latin word mole = heap)
A mole is defined as the amount of substance which contains same number of elementary particles (atoms, molecules or ions) as the number of atoms present in 12 g of carbon (C-12).
1 mol = 6.023 * 1023 atoms = one gram-atom = gram atomic mass
1 mol = 6.023 * 1023 molecules = gram molecular mass
In gaseous state at STP (T = 273 K, p = 1 atm)
Gram molecular mass = 1 mol
= 22.4 L = 6.022 * 1023 molecules
Standard number 6.023x 1023 is called Avogadro number in honour of Avogadro (he did not give this number) and is denoted by NA.
The volume occupied by one mole molecules of a gaseous substance is called molar volume or gram molecular volume.
Number of moles = amount of substance (in gram) / molar mass
Posted by Aadya Singh 3 years, 11 months ago
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Posted by Royal Thakur ? 3 years, 11 months ago
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Aadya Singh 3 years, 11 months ago
Posted by Aadya Singh 3 years, 11 months ago
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Aadya Singh 3 years, 11 months ago
Aadya Singh 3 years, 11 months ago
Posted by Royal Thakur ? 3 years, 11 months ago
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Aadya Singh 3 years, 11 months ago
Posted by Royal Thakur ? 3 years, 11 months ago
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Aadya Singh 3 years, 11 months ago
Posted by Aadya Singh 3 years, 11 months ago
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M. Pranathi 3 years, 11 months ago
Posted by सत्य सनातन? 3 years, 11 months ago
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Gaurav Seth 3 years, 11 months ago
Zero Overlapping of Atomic Orbital – When the orientation of two interacting atomic orbital is such that there is no overlapping of the orbital, that is known as zero overlapping.
The unsymmetrical overlap of orbitals results in zero overlap i-e; between px-s and pxpy orbital
Posted by Aadya Singh 3 years, 11 months ago
- 3 answers
Gaurav Seth 3 years, 11 months ago
Lewis concept
According to him:
Acids: They are those which accept a pair of electron.
For example: substances that falls in this category:
- Cations like ammonium ion etc
- All neutral electron deficient compounds like BF3, AlCl3 etc
- All those which have empty d orbital like SF4 etc
- All those different elements with different electro-negativities but bonded with multiple bonds like carbon dioxide etc.
Posted by Aadya Singh 3 years, 11 months ago
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Aadya Singh 3 years, 11 months ago
Gaurav Seth 3 years, 11 months ago
Atomic or molecular chemical species having a highly localized HOMO (The Highest Occupied Molecular Orbital) act as Lewis bases. These chemical species have the ability to donate an electron pair to a given Lewis acid in order to form an adduct, as discussed earlier. The most common Lewis bases are ammonia, alkyl amines, and other conventional amines. Commonly, Lewis bases are anionic in nature and their base strength generally depends on the pKa of the corresponding parent acid. Since Lewis bases are electron-rich species that have the ability to donate electron-pairs, they can be classified as nucleophiles. Similarly, Lewis acids can be classified as electrophiles (since they behave as electron-pair acceptors).
Posted by Aadya Singh 3 years, 11 months ago
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Gaurav Seth 3 years, 11 months ago
The dipole moment of NH3 is higher in comparison to NF3.
REASON
The F i.e. fluorine is more electronegative than N and pulls the electrons . As the number NF bonds is 3 the 3 F atoms pull the electrons. The resulting electronegative forces decrease the dipole moment.
Posted by Shubham Sachdeva 3 years, 7 months ago
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Sia ? 3 years, 7 months ago
Posted by Parth Suthar 3 years, 11 months ago
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Posted by Farhaan Alam 3 years, 11 months ago
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Sachi Chauhan 3 years, 11 months ago
Posted by V Hayagrish 3 years, 11 months ago
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Yogita Ingle 3 years, 11 months ago
Le Chatelier's principle states that when a system in chemical equilibrium is disturbed by a change of temperature, pressure, or a concentration, the system shifts in equilibrium composition in a way that tends to counteract this change of variable.
Posted by Tannu Sharma 3 years, 11 months ago
- 1 answers
Yogita Ingle 3 years, 11 months ago
Aufbau principle tells us that the lowest energy orbitals get filled by electrons first. After the lower energy orbitals are filled, the electrons move on to higher energy orbitals. The problem with this rule is that it does not tell about the three 2p orbitals and the order that they will be filled in.
According to Hund’s rule:
- Before the double occupation of any orbital, every orbital in the sub level is singly occupied.
- For the maximization of total spin, all electrons in a single occupancy orbital have the same spin.
An electron will not pair with another electron in a half-filled orbital as it has the ability to fill all its orbitals with similar energy. Many unpaired electrons are present in atoms which are at the ground state. If two electrons come in contact they would show the same behaviour as two magnets do. The electrons first try to get as far away from each other as possible before they have to pair up.
</a>Posted by Aadya Singh 3 years, 11 months ago
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Posted by Priyanshu Kumar 3 years, 11 months ago
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Gaurav Seth 3 years, 11 months ago
1. Valency is the maximum no. of electrons which an atom can lose or gain while oxidation no. is the actual no. of electrons which the element lose or gain to form a molecule.
2. Valency is the property of an isolated atom while oxidation state is calculated for an atom is present in a molecule i.e, in a bonded state.
3. Valency of an element remains the same while its oxidation state may be different in different molecules.
Posted by सत्य सनातन? 3 years, 11 months ago
- 2 answers
Vinay Verma 3 years, 11 months ago
Yogita Ingle 3 years, 11 months ago
Spontaneous process. A process which has a natural tendency to take place either by itself or after initiation under a given set of conditions is known as a spontaneous process. For example,
(i) Sugar dissolve in water and forms a solution.
Sugar + water →Solution of sugar in water
Posted by ?Ritesh Gupta? 3 years, 11 months ago
- 1 answers
Yogita Ingle 3 years, 11 months ago
Molecular mass of an element is defined as the sum of the masses of the elements present in the molecule. Molecular mass is obtained by multiplying the atomic mass of an element with the number of atoms in the molecule and then adding the masses of all the elements in the molecule. Let us see an example: carbon dioxide.
The molecular mass of carbon dioxide CO2 = atomic mass of carbon + 2 × (atomic mass of oxygen)
= 12.011 u + 2 × (16.00 u)
= 44.011 u
Posted by Shubhi Jain 3 years, 11 months ago
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Sachi Chauhan 3 years, 11 months ago
Posted by Krishna Sharma 3 years, 11 months ago
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Yogita Ingle 3 years, 11 months ago
In the Lewis structure, the outermost orbit electrons of each atom is shown. The Lewis structure for CO32− is shown in the figure.
Kundan Kumar 3 years, 11 months ago
Posted by Sanjeev Kumar 3 years, 11 months ago
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Harjit Singh 3 years, 11 months ago
Posted by Yug Patel 3 years, 11 months ago
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Yogita Ingle 3 years, 11 months ago
Half-filled atomic orbitals containing electrons with opposite spin.
Posted by Yug Patel 3 years, 11 months ago
- 2 answers
Yogita Ingle 3 years, 11 months ago
Only the electrons present in the outer shell, also known as the valence electrons take part in the formation of chemical bonds.
Posted by Yug Patel 3 years, 11 months ago
- 1 answers
Tanisha Chawla 3 years, 11 months ago
Posted by Tanisha Chawla 3 years, 11 months ago
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Gaurav Seth 3 years, 11 months ago
Born Haber process or more commonly referred to as Born Haber cycle is a method that allows us to observe and analyze energies in a reaction. It mainly helps in describing the formation of ionic compounds from different elements. The methodology further enables us to understand the overall reaction process through a series of steps.
Born-Haber cycle was introduced in the year 1919 by German scientists named Fritz Haber and Max Born. Born Haber cycle is mainly used to calculate the lattice energy. It also involves several steps or processes such as electron affinity, ionization energy, sublimation energy, the heat of formation and dissociation energy
Posted by Tanisha Chawla 3 years, 11 months ago
- 1 answers
Yogita Ingle 3 years, 11 months ago
∆rH for a reaction is defined as the difference between ∆fH value of products and ∆fH value of reactants.
∆H is negative for exothermic reactions which evolve heat during the reaction and∆H is positive for endothermic reactions which absorb heat from the surroundings.
Posted by Tanisha Chawla 3 years, 11 months ago
- 3 answers
Gaurav Seth 3 years, 11 months ago
| Effusion | Diffusion |
| Effusion is said to occur when gas molecules escape through a pinhole into a vacuum. | During diffusion one gas mixes with another usually by thermal random motion resulting in the collision between each other while releasing molecular energy. |
| Effusion in simple terms is the ability of gas to travel through a small opening. | Diffusion is the ability of gases to mix with each other usually in the absence of a barrier. |
| Effusion occurs when the size or aperture of the hole is smaller than the mean free path of the molecules. | Diffusion happens when there are no holes or if holes in the barrier are larger than the mean free path. |
| During effusion particles move faster than diffusion because there is no collision between molecules. | Diffusion rate is limited by the size and kinetic energy of the other particles. |
| Effusion occurs or is facilitated by a difference of pressures. | Diffusion occurs due to difference in concentrations. |
Yogita Ingle 3 years, 11 months ago
| Effusion | Diffusion |
| Effusion is said to occur when gas molecules escape through a pinhole into a vacuum. | During diffusion one gas mixes with another usually by thermal random motion resulting in the collision between each other while releasing molecular energy. |
| Effusion in simple terms is the ability of gas to travel through a small opening. | Diffusion is the ability of gases to mix with each other usually in the absence of a barrier. |
| Effusion occurs when the size or aperture of the hole is smaller than the mean free path of the molecules. | Diffusion happens when there are no holes or if holes in the barrier are larger than the mean free path. |
| During effusion particles move faster than diffusion because there is no collision between molecules. | Diffusion rate is limited by the size and kinetic energy of the other particles. |
| Effusion occurs or is facilitated by a difference of pressures. | Diffusion occurs due to difference in concentrations. |
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?Ritesh Gupta? 3 years, 11 months ago
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