When an electrophile such as H⁺ approaches an alkene molecule, the π electrons are instantaneously shifted to the electrophile and a new bond is formed between carbon and hydrogen. is makes the other carbon electron decient and· hence it acquires a positive charge.

Ozone is formed by a series of reactions that occur from the sun shines

Osmotic pressure of urea solution (\(\pi_1\)) = CRT
\(={W_2\over M_2V}RT\)
\(={6\over 60\times 1}\times RT\)
Osmotic pressure of glucose solution \((\pi_2)={W_2\over 180\times 1}\times RT\) For isotonic solution,
\(\pi_1=\pi_2\)
\({6\over 60}RT={W_2\over 180}RT\)
\(\Rightarrow W_2={6\over 60}\times 180\)
\(W_2=18\ g\)

2 NO(g) + O₂ (g) ⇌ 2NO₂(g)

	NO2	O2	NO2
Initila Partial Pressure	1	1	-
Reacted	0.96	0.96	-
Equilibrium Partial Pressure	0.04	0.52	0.96

\(K_p={P^2_{NO_2}\over P^2_{NO_2}.Po_2}\)
\(={0.96\times 0.96\over 0.04\times 0.04\times 0.52}\)
= 11.07 x 10² (atm)^-1
K_eq = 41.6 x 10² M^-1.

(i) Effective nuclear charge: As the nuclear charge increases, electronegativity also increases along the periods.
(ii) Atomic radius: The atoms in smaller size will have larger electronegativity.

Molar mass of HNO₃ = 1 + 14 + 3 x 16 = 63
Basicity of HNO₃ = 1
Equivalent mass of HNO₃ = \(\frac { 63 }{ 1 } =63g\) eq^-1

The assumption that molecules in the gas phase occupy negligible volume (1) and that they do not exert any force on one another either attractive or repulsive (2) do not account for the behaviour of real gas.

Energy electrons symmetry
This is due to the symmetrical distribution and exchange energy of given d- electrons. Symmetry leads to stability.
Exchange energy:
If two or more electrons with the same spin are present in degenerate orbitals, there is a possibility for exchanging their positions. During exchange process, the energy is released and the released energy is called exchange energy. If more number of exchanges are possible, more exchange energy in released. More number of exchanges are possible only in case of half filled and fully filled configurations.
For example, in chromium the electronic configuration is [Ar]3d⁵ 4s¹. The 3d orbital is half filled and there are ten possible exchanges as shown in figure. On the other hand only six exchanges are possible for [Ar]3d⁴ 4s² configuration. Hence, exchange energy for the half filled configuration is more. This increases the stability of half filled 3d orbitals.

The exchange energy is the basis for Hund's rule, which allows maximum multiplicity, that is electron pairing is possible only when all the degenerate orbitals contain one electron each.

It is the most widely used method for the purification of solid organic compound. This process is carried out in by the following steps:
(i) Selection of Solvent :
Most of the organic substances being covalent do not dissolve in polar solvents like water, hence selection of solvent (suitable) becomes necessary. Hence the powdered organic substance is taken in a test tube and the solvent is added little by little with constant stirring and heating, till the amount added is just sucient to dissolve the solute(ie) organic compound. If the solid dissolves upon heating and throws out maximum crystals on cooling, then the solvent is suitable. This process is repeated with other solvents like benzene, ether, acetone and alcohol till the most suitably one is sorted out.
(ii) Preparation of solution: The organic substance is dissolved in a minimum quantity of suitable solvent. Small amount of animal charcoal can be added to decolorize any colored substance. The heating may be done over a wire gauze or water bath depending upon the nature of liquid (ie) whether the solvent is low boiling or high boiling.
(iii) Filtration of hot solution: The hot solution so obtained is filtered through a fluted filter paper placed in a funnel.
(iv) Crystafhzation: The hot filtrate is then allowed to cool. Most of the impurities are removed on the Iter paper, the pure solid substance separate as crystal. When copious amount of crystal has been obtained, then the crystallization is complete. If the rate of crystallization is slow, it is induced either by scratching the walls of the beaker with a glass rod or by adding a few crystals of the pure compounds to the solution.
(v) solation and drying crystals: The crystals are separated from the mother liquor by filtration. Filtration is done under reduced pressure using a Bucher funnel. When the whole of the mother liquor has been drained into the filtration flask, the crystals are washed with small quantities of the pure cold solvent and then dried.

S_N2 Mechanism :
(i) The rate of S_N2 reaction depends upon the . concentration of both alkyl halide and the nucleophile.
(ii) Rate of reaction = is [alkylhalide] [nucleophile]. It follows second order kinetics and occurs in one step. 
(iii) This reaction involves the formation of a transition state in which both the reactant molecules are partially bonded to each other. The attack of nucleophile occurs from the back side (i.e opposite to the side in which the halogen is attacked).
(iv) The carbon at which substitution occurs has inverted configuration during the course of reaction just as an umbrella has tendency to invert in a wind stonri. is inversion of configuration is called Walden inversion; after paul walden who 1st discovered the inversion of configuration of a compound in S_N2reaction.
(v) S_N2reaction of an optically active haloalkane . is always accompanied by inversion of configuration at the asymmetric centre.
(vi) When 2 - Bromooctane is heated with sodium hydroxide, 2 - octanol is formed with invesion of configuration. (-) - 2 - Bromo octane is heated with sodium hydroxide (+) - 2 - Octanol is formed in which - OR group occupies a position opposite to what bromine had occupied,

(a) (-).2 - Bromo octane
(b) Transition State
(c) (+) 2 - Octanol (product)

w = 0.24g and a = 0.287 g
\( \% \mathrm{Cl} =\frac{35.5}{143.5} \times \frac{\mathrm{a}}{\mathrm{w}} \times 100 \)
\(=\frac{35.5}{143.5} \times \frac{0.287}{0.24} \times 100=.29 .42 \%\)

Zn + NO₃^- ⟶ Zn + NH₄⁺² in basic medium
Zn ⟶ Zn⁺² + 2e (oxidation) NO₃^- ⟶ NH₄⁺ (Reduction)
Step-1: Balance all atoms other than hydrogen and oxygen.
Zn ⟶ Zn⁺²       NO₃^- ⟶ NH₄⁺
Step-2: For balancing oxygen atom in alkaline medium, add H20 molecules on the side deficient of oxygen atom.
Then balance hydrogen atom, add H20 molecule to the side deficient in hydrogen and equal number of OH- on the other side.
Zn ⟶ Zn⁺²       NO₃^- ⟶ NH₄^-+3H₂O
NO₃^- + 10H₂O ⟶ NH₄⁺ + 3H₂O
NO₃^- + 10H₂O ⟶ NH₄⁺ + 3H₂O + 10OH^-
Step-3: Add electrons to balance charge
Zn ⟶ Zn⁺² +2e
NO₃^- + 7H₂O + 8e ⟶ NH₄⁺ +10OH^-
       Zn ⟶ Zn+2 + 2e x 8
NO3- + 7H2O + 8e ⟶ NH4+ + 10OH-
___________________________________
8Zn + NO₃^- + 7H₂O ⟶ 8Zn⁺² + NH₄⁺ + 10OH^-
This is the balanced equation.

(i) The deviation of real gases from ideal behaviour is measured in terms of a ratio of PV to nRT. This is termed as compression factor. Mathematically,
\(Z=\frac { PV }{ nRT } \)
For ideal gases Z=1 at all temperatures and pressures, because PV = nRT.
(ii) When a gas deviates from ideal behaviour, its Z value deviates from unity.
(iii) At high pressure these gases have Z > 1 and are difficult to compress. At intermediate pressures, Z< 1.
(iv) Above the Boyle point, Z > 1 for real gases, ie., the real gases show positive deviation.
(v) Below the Boyle point, the real gases first show a decrease for Z, reaches a minimum and then increase with the increase in pressure.
Hence, the compressibility factor Z can be rewritten as
\(Z=\frac { { PV }_{ real } }{ nRT } \)
\({ V }_{ ideal }=\frac { nRT }{ P } \)
Substituting b in a
\(Z=\frac { { V }_{ real } }{ { V }_{ ideal } } \)
(vi) Where V_real  is the molar volume of the real gas and V_ideal is the molar volume of it when it behaves ideally.

(a) Isothermal process: An isothermal process is defined as one in which the temperature of the system remains constant, during the change from its initial to final state. The system exchanges heat with its surroundings and the temperature of the system remains constant.  
For an isothermal process dT = 0
(b) Adiabatic process: An adiabatic process is defined as one in which there is no exchange of heat (q) between the system and surrounding during the process. For an adiabatic process q = 0
(c) Isobaric process: An isobaric process is defined as one in which the pressure of the system remains constant during its change from the initial to final state. For an isobaric process dP = 0 .
(d) Isochoric process: An isochoric process IS defined as the one in which the volume of system remains constant during its change from initial to final state. For an isochoric process, dV= 0.

(i) Magnesium and calcium also play a vital role in biological functions. A typical adult human body contains about 25 g of magnesium and 1200 g of calcium. Magnesium plays an important· role in many biochemical reactions catalysed by enzymes. It is the co-factor of all enzymes that utilize ATP in phosphate transfer and energy release. It is also essential for DNA synthesis and is responsible for the stability and proper functioning of DNA.It is also used for balancing electrolytes in our body. Deficiency of magnesium results into convulsion and neuromuscular irritation.
(ii) Calcium is a major component of bones and teeth. It is also present in blood and its concentration is maintained by hormones (calcitonin and parathyroid hormone). Deficiency of calcium in blood causes it to take longer time to clot. It is also important for muscle contraction.
(iii) The main pigment that is responsible for photosynthesis, chlorophyll, contains magnesium which plays an important role in photosynthesis.

(i) Electron configuration of nitrogen
(Z = 7) 1s² 2s² 2p³.
Electron configuration of oxygen
(2= 8) 1s² 2s² 2p⁴.
Nitrogen has a half filled electronic configuration which is much more stable than an incomplete p-orbital of oxygen which would need to give up one of it's electrons to attain the stability of nitrogen. Hence nitrogen would require more ionization energy to remove an electron from it's outer shell than oxygen.
(ii) Electron configuration of carbon
(Z = 6) 1s²2s²2p².
Electron configuration of Boron
(Z = 5) Is²2s²2p¹
The size of a carbon atom is smaller than boron So the valence electron of carbon has greater nuclear charge than that of boron. Hence the first I.E of carbon is greater than that of boron. However, the second ionization enthalpy of boron is higher than that of carbon. This is because after losing electron, Boron has a fully filled orbital (2s²) than carbon (2p¹). Fully filled orbitals have more stability than partially filled orbitals so greater amount of energy will be needed to remove an electron from boron. So in this case, the second I.E of boron is higher than that of carbon.
(iii) The electron affinities of Be, Mg and noble gases are almost zero because both Be (Z = 4; 1s²2s²) and Mg (Z = 12; Is²2s²2p⁶3s²) are having s orbital fully filled in their valence shell. Fully filled orbitals are most stable due to symmetry. Therefore, these elements would be having least tendency to accept electron. Hence, Be and Mg would be having zero electron affinity. Whereas N (Z = 7; 1s²2s²2px¹2py¹2pz¹ and P (Z = 15) Is² 2s² 2p⁶ 3s² 3p³ is having half filled 2p-subshell. Half filled sub shells are most stable due to symmetry (Hund's rule). Thus, nitrogen and phosphorous are having least tendency to accept electron. Hence, have low electron affinity.
(iv) Fluorine is highly electro negative in nature therefore as it gains the electron its octet become stable and releases the energy so exothermic. while in oxygen the addition of first electron is exothermic in nature but addition of second electron experiences high repulsive force. So needs extra external energy to enter outer shell, hence endothermic in nature.

(i) By treatment with catalyst like Pt or Fe.
(ii) By passing an electric discharge
(iii) By heating to 800°C or more.
(iv) By mixing with paramagnetic molecules like O₂,NO,NO₂·
(v) By mixing with nascent hydrogen or atomic hydrogen.

An atom or a group of atoms present in an organic compound, which is responsible for the chemical properties of the compound is called the functional group.

The exothermic nature of alkane combustion reaction explains the extensive use of alkanes as fuels. Methane present in natural gas is used in home heating. Mixture of propane and butane are known, as LPG gas which is used for domestic cooking purpose. GASOLINE is a complex mixture of many hydrocarbons used as a fuel for internal-combustion engines.
Carbon black is used in the manufacture of ink, printer ink and black pigments. .It is also used as fillers.

No of Carbon Atoms	State at room temperature	Major uses
1-4	Gas	Heating fuel, Cooking fuel
5-7	Low boiling liquid	Solvents, Gasoline
6-12	Liquid	Gasoline
12-24	Liquid	Jet fuel- portable stove fuel
18-50	High boiling liquid	Diesel fuel, lubricant, heating oil
50+	Solid	Petroleum jelly and paran wax

Standard characteristics of drinking water.

S.No	Characteristics	Desirable limit
I	Physico-chemical Characteristics
i)	pH	6.5 to 8.5
ii)	Total Dissolved Solids (TDS)	500ppm
iii)	Total Hardness (as CaCO3)	300 ppm
iv)	Nitrate	45ppm
v)	Chloride	250ppm
vi)	Sulphate	200ppm
vii)	Fluoride	1 ppm
II	Biological Characteristics
i)	Escherichia Coli (E.Coil)	Not at all
ii)	Coliforms	Not to exceed 10 (In 100 ml water sample)

With acetyl chloride, CH₃MgI given first acetone.

The acetone formed will react with excess CH₃MgI to give a tertiary alcohol, t - butyl alcohol.

\(\Delta n_{g}=\sum n p_{(g)}-\sum n R_{(g)}\)
As \(\Delta n_{p}(g)\) is greater \(\Delta n_{g}=+v e\)
\( \therefore K_{p}=K_{c}(R T)^{+v e} \)
\(\therefore K_{p}>K_{c} \)
So K is smaller than K_p.

The balanced stoichiometric equation for the formation of ammonia is
N₂(g) + 3H₂ (g) \(\rightarrow\) 2NH₃ (g)
As per the stoichiometric equation,
To produce 2 moles of ammonia, 3 moles of hydrogen are required.
\(\therefore\)  to produce 10 moles of ammonia,

= 15 moles of hydrogen are required.

(i) O or F. Both O and F lie in 2^nd period. As we move from O to F the atomic size decreases. Due to smaller size of F nuclear charge increases.
Further, gain of one electron by
\(F\rightarrow F^-\)
ion has inert gas configuration, While tile gain of one electron by
\(O\rightarrow O^-\)
gives O^- ion which does not have stable inert gas configuration. Consequently, the energy released is much higher in going from
\(F\rightarrow F^-\)
than going from\(O\rightarrow O^-\). In other words electron gain enthalpy of F is much more negative than that of oxygen.
(ii) The negative electron gain enthalpy of CI \((e.g.\triangle H=-349\ kJ\ mol^{-1})\) is more than that of \(F(e.g.\triangle H=-328\ kJ\ mol^{-1})\) 
The reason for the deviation is due to the smaller size of F. Due to its small size, the electron repulsions in the relatively compact 2p-subshell are comparatively large and hence the attraction for incoming electron is less as in the case of Cl.

'U' is an extensive property because its magnitude depends on the quantity of material in the system.

V₁ = 8.5 dm³ V₂ = 6.37 dm³
T₁ = ? T₂ = 0^o C = 273 K
\(\frac { { V }_{ 1 } }{ { T }_{ 1 } } =\frac { { V }_{ 2 } }{ { T }_{ 2 } } \)
\({ V }_{ 1 }\times \left( \frac { { T }_{ 2 } }{ { V }_{ 2 } } \right) ={ T }_{ 1 }\)

T₁ = 364.28 K