JEE NEET MATERIALS

2021-07-19 17:14:08 Short-cut technique for balancing a chemical equation
Example:

aCaCO3 + bH3PO4 → cCa3(PO4)2 + dH2CO3

Set up a series of simultaneous equations, one for each element.

Ca: a=3c

C: a=d

O: 3a+4b=8c+3d

H: 3b=2d

P: b=2c

Let’s set c=1

Then a=3 and

d = a = 3

b = 2c = 2

So a=3; b=2; c=1; d=3

The balanced equation is

3CaCO3 + 2H3PO4 → Ca3 (PO4)2 + 3H2CO3

⑉⑉⑉⑉⑉⑉⑉⑉⑉⑉༄༄༄⑉⑉⑉⑉⑉⑉⑉⑉⑉⑉
MUST SHARE WITH FRIENDS IT WILL DELETED WITHIN 12HRS Open / Comment

2021-07-19 14:34:11 Important Notes on P-Block Elements – Nitric Acid

Hyponitric acid does not exist. The rest three mentioned are commonly occurring oxoacids of nitrogen. Hyponitrous acid, H2N2O2 is an isomer tautomer of nitramide, with the structure of the former being HON = NOH. Nitrous acid, HNO2 is usually formed in the atmosphere prior conversion to nitric acid. It is highly unstable.

Nitric acid is a very weak reducing agent since it has a polar O – H bond. This breaks to donate the H+ ion which is why it is a strong oxidizing agent and a strong acid. Since there is only one cleavable O – H bond, the basicity of nitric acid is unity (one HNO3 molecule can donate only 1 H+ ion). It exists as a planar molecule in vapor phase.

The most appropriate lab scale preparation method of nitric acid, HNO3 is using an alkali nitrate salt and react it with concentration nitric acid in a glass retort. Nitrous acid being highly unstable decomposes into nitric acid. The other two sets of reaction represent the industrial process of manufacturing nitric acid i.e. Ostwald’s process.

Ostwald’s process is the name of the industrial process to manufacture nitric acid in bulk. It involves the oxidation of ammonia which forms nitric oxide. This is then reacted with more oxygen to produce nitrogen dioxide. Subsequently, nitrogen dioxide is dissolved in water to produce adequate concentrations of nitric acid. Contact process is used to produce sulfuric acid. Solvay is used to obtain sodium carbonate and Haber-Bosch to obtain ammonia.

Pt-Rh gauze sheet is widely used as the catalyst in ammonic oxidation, the first step of Ostwald’s process. Fe2O3 is used in Haber’s process; V2O5 in contact process and Zn (Hg) is used in Clemmensen reduction of aldehydes.

Experimentally, it is determined that nitric acid and water form a constant boiling azeotrope at 68% – 32% by mass composition, respectively. Here, it becomes impossible to separate water and nitric acid by distillation methods. Thus, concentrated sulfuric acid is used for dehydration and removal of water.

The products released depend on the concentration of nitric acid. In case of zinc metal, diluted nitric acid treatment release nitrous oxide and concentrated nitric acid causes the release of nitrogen dioxide.

Aluminum does not dissolve in nitric acid. This is because treatment with nitric acid results in the formation of a tough oxide layer. This oxide layer prevents it from further reacting with the oxide. Hence, the compound formed is Al2O3 i.e. aluminum (III) oxide.

Pickling of stainless steel is the process of removal of a thin layer of the alloyed metal from the surface. The common reagent used is nitric acid along with calculated amounts of hydrofluoric acid.

1 mole of sulfur, S8 requires 48 moles of concentrated nitric acid. The reaction is given by S8 + 48HNO3 → 8H2SO4 + 48NO2 + 16H2O. 10, 4 and 20 moles of concentrated nitric acid is required to produce iodic acid, carbon dioxide and phosphoric acid from 1 mole of iodine, carbon and phosphorus, respectively
⑉⑉⑉⑉⑉⑉⑉⑉⑉⑉༄༄༄⑉⑉⑉⑉⑉⑉⑉⑉⑉⑉
MUST SHARE WITH FRIENDS IT MIGHT GET DELETED WITHIN 12HRS Open / Comment

2021-07-19 13:46:33 Cell Cycle

𝘾𝙚𝙡𝙡 𝙜𝙧𝙤𝙬𝙩𝙝, DNA replication and cell division constitute a cell 𝙘𝙮𝙘𝙡𝙚

Events happening in a cell cycle is genetically controlled

𝘿𝙪𝙧𝙖𝙩𝙞𝙤𝙣 of cell cycle varies in different organisms and different types of cells. The average duration of the 𝙝𝙪𝙢𝙖𝙣 cell cycle is 24 hrs, whereas a yeast cell completes one cell cycle in 90 𝙢𝙞𝙣𝙪𝙩𝙚𝙨

The cell cycle is 𝙙𝙞𝙫𝙞𝙙𝙚𝙙 into Interphase and M phase

𝙄𝙣𝙩𝙚𝙧𝙥𝙝𝙖𝙨𝙚: Cell growth and replication of DNA. It constitutes 95% of the duration of a cell cycle

𝙈 𝙋𝙝𝙖𝙨𝙚: Mitosis (cell 𝙙𝙞𝙫𝙞𝙨𝙞𝙤𝙣)


𝙎𝙩𝙖𝙮 𝙩𝙪𝙣𝙚𝙙 & 𝙨𝙩𝙖𝙮 𝙨𝙖𝙛𝙚

Open / Comment

2021-07-19 11:19:43 Something intresting Open / Comment

2021-07-19 11:19:18 Open / Comment

2021-07-19 10:21:09 QOTD QUESTION OF THE DAY SEND ANSWER IN
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ALL CORRECT ANSWERS WILL GET A×××N TEST SERIES MEGA LINK AS REWARD ANSWER FAST AND SHARE
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2021-07-19 10:19:40 Open / Comment

2021-07-19 10:07:05 Very Important At This Point Of Time

1. Formulas related to force:
F = ma
F = kx
F = m(vf² - vi²/2S)
F = mv/t
F = md/t²
F = m(vf - vi) /t
F = Area × density × velocity²
F = 1/2 mv²/d
F = 1/2 Pv/d
F = Power/velocity
Fc = mv²/r
Fc = mrw²
Fc/2 = mv²/2r
Fc = 2K.E/r
F = Area × Stress
F = pir² × stress
F = YA × Strain
F = YAl/L
F = pressure × area
F = change in momentum × time interval
F = - 2mVx × Vx/2l
F2 = F1/A1 × A2
F = qE
F = kQ/r²
F = ILB sintheta
F = q (v × B)
F = qE + q(v × B)

2. Formulas related to energy and work
Fd = k.e
mgh = 1/2 mv²
E = 1/2 kx²
E = Ve
E = nhf
E = nhc/lambda
E = Pc
K.e = hf - work function = hf - hf° = hf - hc/w° (here w° is cutt off wavelength)
E = 1/2 Pv
mv²/2r= Fc/2
K.E/r = Fc/2
K.E = Fc×r/2
K.e = 1.5 KT
E = VQ
E = Power × time
E = Fvt
% loss in K.e = v1² - v2²/v1² × 100
% loss in P.e = h1² - h²/h1² × 100
Energy lost due to air friction(Fh) = 1/2mv² - mgh (when body is thrown upward)
Energy lost due to air friction(FS) = mgh - 1/2mv² (when body is thrown downward)
E = 1/2 CV² (capacitor)
E = R × hc (R is Rydberg' constant)
J = m-¹ × Js ms-¹
hf kalpha x rays = EL - Ek
hf kbeta x rays = EM - Ek
Binding energy = mass defect × c²
W = Fd Costheta
W = nmgh (when person is climbing stairs)
W = n(m+m) gh (when person is climbing stairs with some load)
W = 0mgh + 1mgh + 2mgh + 3mgh ....... (in case of stacking bricks. For ist brick h=0. For 2nd brick h=1. For 3rd brick h=2 and so on)
W = Fd = PA × change in V
W = Q - change in U
Q = mc × change in T
T/273.16 = Q/Q3 (Thermodynamic scale)
W = I²Rt
W = emf×charge
W = VQ
W = 1/2 lF
W = YAl²/2L
W = StressAl²/2Strain
W = PressureAl²/2Strain
W = Fl²/2Strain

3. Formulas related to Power
P = Fv
P = E/t
P = n(mgh/t)
P = Fd/t
P = mv²/2t

4. Formulas related to distance, displacement, velocity and accelration
d = vt
d = at²
d = (vf + vi/2) ×t
d = 5t² (for distance in 'n' seconds)
d = 5(2tn - 1) (for distance in 'nth' second)
d = 1/2 mv²/F
d = vit + 5t²
d = v × underroot 2H/g
d = vt = x°wt = x°2pi/T × t = x°2pift
x = x° Sin wt
x = x° Sin (underroot k/m) t
vf = vi + at
2as = vf² - vi²
2as = (vi + at)² - vi²
2as = vf² - (vf - at) ²
v = underroot Vfx² + Vfy²
v = Power/Force
v = 2×K.E/momentum (k.e = 1/2 Pv)
v² = 2×Power×time/mass (P = mv²/2t)
v = underroot 2as
v = underroot gr (speed at highest point in a verticle circle)
v = underroot 5gr (speed at lowest point in a verticle circle)
v² = 2FS/m
v² = 2E/m
v² = 2Ve/m
v = eBr/m (velocity of particle under action of magnetic force along circular path)
v² = Force/Area.Density
v = w underroot x°² - x²
v = underroot k/m × underroot x°² - x²
v = x°w (at mean position where x=0)
v = x° underoot k/m
v = v° underroot 1 - x²/x°² (for determining ratio b/w inst. Velocity and maxi. Velocity)
v= x°2pif = x°2pi/T
a = x°w² = x°w.w = vw = v.2pif
Common velocity = m1v1/m1+m2
vi² = Rg/Sin2theta
v = underoot Tension×length/mass
V = 2pi ke²/nh (speed of e- in nth orbit)
Vn = V/n
v = nh/2pimr (lambda = 2pir and lambda=h/p)
ma = kx
a = kx/m (SHM)
a = - gx/l (Simple pendulum)
ac = v²/r

5. Formulas related to wavelength 'w'
w = v/f
w = 1/wave number
w1 = 2l (when pipe is opened at both ends)
w1 = 4l (when pipe is opened at one end)
Delta w = Us/f (doppler shift)
Wavelength for obs. = w - delta w = v/f - Us/f
w = hc/Ve
w = hc/E
w = h/mv
w = h/P as P = underroot 2mE so
w = h/underroot 2mE (de Broglie wavelength)
w = underroot 150/V A° (short method for de Broglie wavelength. This formula is applicable only for e-)
1/w = RH (1/p²-1/n²)
Wmaxi/Wmini = n²/n²-p² (for determining ratio b/w maxi. Wavelength to mini. Wavelength for series of atomic spectrum)
w = 2pir/n (n is no. of loops in a circle)
h/mv = 2pir Open / Comment

2021-07-19 10:06:18 IMPORTANT POINTS WITH TRICKS :

CADET Face Right -(CO2, ACID, 2,3DPG, EXCERCISE, TEMP RISE - Leads to shifting of oxyhb curve to right)

CHON CaP = (macronutrients) (Carbon,hydrogen,oxygen,nitrogen,calcium and phosphorus)

HARD (Evolution) (homologous organs, adaptive radiation, divergent evolution

Cows often sit down carelessly, perhaps their joints crack, persistent early oiling might prevent painful rheumatism. (Cambriam, ordovician, silurian, devonian, carboniferous, permian, triassic, jurassic, cretaceous periods) (palaeocene, eocene, oligocene, miocene, pliocene, pleistocene, holocene(recent) epoch)

ABC - anthrax, bacilluc, clostridium (all reproduce by endospores)

Reserve bank of india - reptiles, birds, insects (all uricotellic)

FIG COM = female lives in gynaecophoric canal of male
children like granny speaking german - layers if skin

STRATUM (corneum, lucidum, granulosum, spinosum, germinativum/malphigi) Open / Comment