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Ask QuestionPosted by Rohit Rai 3 years, 10 months ago
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Posted by A Thelei 3 years, 10 months ago
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Aadya Singh 3 years, 10 months ago
Both O2 n O2+ is paramagnetic .
Posted by Madhur Kumar 3 years, 10 months ago
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Gaurav Seth 3 years, 10 months ago
Optical isomerism is basically a type of stereoisomerism. Now, before we learn about optical isomerism let us quickly recall what are isomers and stereoisomers. Isomers are those compounds which have the same molecular formula but different bonding arrangement among atoms.
Whereas, in stereoisomer, both molecular formula and bonding arrangement of atoms are the same. However, they have different spatial (three dimensional) arrangement of atoms. It eliminates all different arrangements that are simply due to the molecule spinning in its entirety or revolving around unique bonds.
Posted by Ekta Rajput 3 years, 10 months ago
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Yogita Ingle 3 years, 10 months ago
The higher the magnitude of lattice energy, the stronger the ionic bond formed. This is because more energy is released when strong bonds are formed.
Posted by Pk✍️ . 3 years, 10 months ago
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Yogita Ingle 3 years, 10 months ago
- Where one-colour merges into another and there is no definite boundaries, that spectra is called continuous spectra.
- If we study it for atoms the spectra obtained is discontinuous spectra.
- The study of spectra is called spectroscopy
Posted by Punam Ingale ?? 3 years, 10 months ago
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Yogita Ingle 3 years, 10 months ago
Some important applications of this branch of chemistry are listed below.
- The shelf lives of many medicines are determined with the help of analytical chemistry.
- It is used to check for the presence of adulterants in drugs.
- Soil can be tested to check for appropriate concentrations of minerals and nutrients that are necessary for plant growth.
- It is employed in the process of chromatography where the blood samples of a person are classified.
Posted by Sourav Singh 3 years, 10 months ago
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Madhur Kumar 3 years, 10 months ago
Gaurav Seth 3 years, 10 months ago
Ans: Cs
Among alkali metals, melting point decreases as the strength of metallic bonding decreases with increasing size of the atom. Thus, Cs has the lowest melting point (28.5°C) and will melt at 30°C.
Posted by Akshat Anand 3 years, 10 months ago
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Gaurav Seth 3 years, 10 months ago
i.
ANSWER
The manufacture of ammonia by Haber's process is an exothermic reaction. According to Le Chatelier's principle maximum yield of an exothermic reaction can be obtained at low temperatures. There are 4 molecules on reactant side and 2 on product side. According to Le Chatelier's principle if you increase the pressure the system will respond by favouring the reaction which produces fewer molecules. So the maximum yield of ammonia will be obtained at high pressure and low temperature
Posted by Punam Ingale ?? 3 years, 10 months ago
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Gaurav Seth 3 years, 10 months ago
Chromatography: It is a technique used to separate mixtures in to their components, purify. Compounds which can be solid or liquid and also test the purity of compounds.
- In this technique the mixture of substances are applied on to a stationary phase .Then a pure solvent or a mixture of solvents is allowed to move slowly over stationary phase .The components of mixture gets gradually separated from one another .The moving phase is mobile phase .
The chromatography is classified into two categories:
- Adsorption chromatography
- Partition chromatography
Posted by ?Ritesh Gupta? 3 years, 11 months ago
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Posted by Charanpreet Khaira 3 years, 11 months ago
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Gaurav Seth 3 years, 11 months ago
Diamond
It can also be prepared artificially but because of the high cost and poor quality, diamonds are seldom made artifically.
Structure
In diamond , carbon is sp3– hybridised . Each carbon is tetrahedrally linked to four neighbouring carbon atoms through four strong C-C , sp3– sp3 , σ bonds. This network extends in three dimensional and is very rigid.
Posted by ?Ritesh Gupta? 3 years, 11 months ago
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Aayushi Chauhan 3 years, 11 months ago
Posted by Shruti Kesharwani 3 years, 11 months ago
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Posted by Aniket Ranjan 3 years, 11 months ago
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Yogita Ingle 3 years, 11 months ago
Work done on an ideal gas can be calculated from p-V graph shown in Fig. Work done is equal to the shaded area ABVIVII .
Posted by Aniket Ranjan 3 years, 11 months ago
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Gaurav Seth 3 years, 11 months ago
ANSWER
The average kinetic energy of a collection of gas particles is directly proportional to absolute temperature only.
We know that, KE = 3 / 2 kT
where 3 / 2 k , so KE ∝ T
Now we can say that the average kinetic energy of a gas molecule at absolute temperature T is directly proportional to T.
Yogita Ingle 3 years, 11 months ago
The average kinetic energy of the particles in a gas is proportional to the temperature of the gas
Posted by M. Pranathi 3 years, 11 months ago
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Gaurav Seth 3 years, 11 months ago
The actual charge felt by the valence shell electron is called effective nuclear energy. It is denoted by
zeff and the repulsive forces felt by valence shell electrons from the electron present in the inner shell is called shielding effect or screening effect.
zeff = total nuclear charge − screening constant (σ)
Screening constant = total nuclear charge − zeff
Greater the number of electrons in inner shells larger will be the screening effect. With increase in screening effect zeff will be decreased.
As the force of attraction by the nucleus for the valence shell electrons decreases and hence the ionization energy decreases. In other words an increase in the number of electrons in the inner shell leads to decrease the ionization energy.
Yogita Ingle 3 years, 11 months ago
The electrons present in the inner shells act as screens between the nucleus and the valence shell electrons. In order words, these electrons partially neutralise the force fo attraction fo the nucleus, over the valence electrons. This is called, 'shielding or screening effect'.
When the screening effect increase (No. of inner electron-shells increase), the IP decreases.
THe magnitude of screening effect ∝1/I.P.
Posted by Pk✍️ . 3 years, 11 months ago
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Yogita Ingle 3 years, 11 months ago
Geometrical isomerism is a type of stereoisomerism having the same molecular formula and same structure but differ in the relative arrangement of atoms.
An example of geometric isomerism you will meet at an introductory level is but-2-ene. In one case, the CH3 groups are on opposite sides of the double bond, and in the other case, they are on the same side. The two most common types of geometric isomers are those arising from a double bond and those arising from a ring structure. These type of geometric isomers are also called cis/trans isomers. When two identical groups occupy adjacent positions, the isomer is called cis and when arranged opposite to one another, the isomer is called trans. e.g[Pt(NH3)2Cl2]
Posted by ?Ritesh Gupta? 3 years, 11 months ago
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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
Posted by Heena Bilam 3 years, 11 months ago
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Posted by Atharva Verma 3 years, 11 months ago
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Anmol Agarwal 3 years, 11 months ago
Yogita Ingle 3 years, 11 months ago
Enthalpy of atomization, ΔaH0, is the change in enthalpy when one mole of bonds is completely broken to obtain atoms in the gas phase. For example: atomization of methane molecule.
CH4 (g) → C (g) + 4H (g) ΔaH0= 1665.0 kJ mol-1
For diatomic molecules, enthalpy of atomization is equal to the enthalpy of bond dissociation. For example: atomization of dihydrogen molecule.
H2 (g) → 2H (g); ΔaH0= 435.0 kJ mol-1
Posted by Parisha Dahiya 3 years, 11 months ago
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Posted by Sarthak Shrivastava 3 years, 11 months ago
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Yogita Ingle 3 years, 11 months ago
Suppose no. of atoms Y present in the packing = n
Atoms X present in the tetrahedral voids =1/3×2n = 2n/3
Ratio of X :Y =2n/3:n=2/3 :1 = 2:3
Hence, the formula is X2Y3
Posted by Aadya Singh 3 years, 11 months ago
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Anmol Agarwal 3 years, 11 months ago
Posted by Sweety Singh 3 years, 11 months ago
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Anmol Agarwal 3 years, 11 months ago
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Yogita Ingle 3 years, 10 months ago
The boiling point for Gallium stands at approximately 2200 degrees Celsius, and its density is 5.907 grams per cubic centimetre which is high like the density of water.
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