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Class 12th Organic Chemistry - Some Basic Principles and Tech

The major product 'A' of the following given reaction has _________ sp² hybridized carbon atoms.

2, 7-Dimethyl 1-2-6- octadiene A

Major Product

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Vishal Baghel

Contributor-Level 10

Number of sp² hybridized carbon in A = 2

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Class 12th Organic Chemistry - Some Basic Principles and Tech

Number of electrophilic centres in the given compounds is _________.

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Vishal Baghel

Contributor-Level 10

Kindly consider the following figure

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Class 12th Organic Chemistry - Some Basic Principles and Tech

A 0.166 g sample of an organic compound was digested with conc. H₂SO₄ and then distilled with NaOH. The ammonia gas evolved was passed through 50.0 mL of 0.5 N H₂SO₄. The used acid required 30.0 mL of 0.25 N NaOH for complete neutralization. The mass percentage of nitrogen in the organic compound is ___________.

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Vishal Baghel

Contributor-Level 10

Meq of NH₃ = Meq of used H₂SO₄ = Meq of NaOH = 0.25 * 30 = 7.5

Millmoles of N = millimoles of NH₃ = 7.5 (As n factor = 1)

Mass of nitrogen = 7.5 * 14 * 10^-3 = 0.105 gm

% of Nitrogen = $\frac{0.105}{0.166} * 100 % = 63.25 % ~ 63 %$

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Class 12th Coordination Compounds

In the cobalt-carbonyl complex : [Co₂(CO)₈], number of Co-Co bonds is “X” and terminal CO lignads is “Y”. X + Y = __________.

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Vishal Baghel

Contributor-Level 10

Number of Co-Co Bond = X = 1

Number of terminal ligand = Y = 6

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Class 12th Maths

Let the plane ax + by + cz = d pass through (2, 3, -5) and its perpendicular to the planes

2x + y – 5z = 10 and 3x + 5y – 7z = 12.

If a, b, c, d are integers d > 0 and then the value of a + 7b + c + 20d is equal to:

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alok kumar singh

Contributor-Level 10

ax + by + cz = d

2a + 3b – 5c = d 2a + 3b – 5c = d …………….(v)

Putting (i) & (iv) in (v) we get a = -9d.

In conditions

$(2 \hat{i} + \hat{j} - 5 \hat{k}), (a \hat{i} + b \hat{j} + c \hat{k}) = 0$

2b = d ………….(i) d > 0

2a + b – 5c = 0 2a + 3b – 5c = d $| a |, | b |, | c |, d \to g . c . d$

= $\frac{α}{2}$

$∴ \frac{α}{2} = 1 \Rightarrow α = 2$

$(3 \hat{i} + 5 \hat{j} - 7 \hat{k}) . (a \hat{i} + b \hat{j} + c \hat{k}) = 0$

3a + 5b – 7c = 0) * $\frac{4}{7} . . . . . . . . . . . . . . . . . . . (i i i)$

$∴ a = - 18, b = 1$

c = -7, d = 2

(iii)…(ii) ® 2a + 3b $\frac{- 33 c}{7} = 0$

2a + 3b = $\frac{33}{7} c$ $c = \frac{- 7}{2} d . . . . . . . . . . . . . . . . . (i v)$

Putting values

a + 7b + c + 20d = 22

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Class 12th Coordination Compounds

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Vishal Baghel

Contributor-Level 10

Number of Co-Co Bond = X = 1

Number of terminal ligand = Y = 6

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6 months ago

Class 12th Chemistry

The difference in oxidation state of chrominum in chromate and dichromate salts is _________.

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Vishal Baghel

Contributor-Level 10

Kindly consider the following figure

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6 months ago

Class 12th Chemistry

The difference in oxidation state of chrominum in chromate and dichromate salts is _________.

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6 months ago

Class 12th Maths

If vertex of a parabola is (2, -1) and the equation of its directrix is 4x – 3y = 21, then the length of its latus rectum is:

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alok kumar singh

Contributor-Level 10

$a = | \frac{4.2 - 3 (- 1) - 21}{5} |$

$= | \frac{8 + 3 - 21}{5} | = 2$

$∴ L = 4 a = 8$

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Class 12th Chemistry Chemical Kinetics

The rate constants for decomposition of acetaldehyde have been measured over the temperature range 700 – 1000 K. The data has been analysed by plotting ln k vs $\frac{1 0^{3}}{T}$ graph. The value of activation energy for the reaction is ___________ kJ mol^-¹.

(Nearest integer)

(Given : R = 8.31 J K^-¹ mol^-¹)

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Vishal Baghel

Contributor-Level 10

$k = A . e^{- (\frac{E a}{R T})}$

$l n k = l n A - \frac{E a}{R T}$

$\Rightarrow l n k = l n A + (- \frac{E a}{1000 R}) . \frac{1000}{T}$

Slope = $\frac{- E a}{1000 R} = - 18.5$

=> Ea = 18.5 * 1000 * 8.31 = 153.735 * 10³ J = 154 KJ

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