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why do phenols have more boiling point than alcohols of comparable molecular mass

Posted by R.Sasi Kumar 2 years, 10 months ago

CBSE > Class 12 > Chemistry

3 answers

Alok Mittal 2 years, 9 months ago

In simple we write only this Is because of resonance effect

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Anjan Karthi 2 years, 10 months ago

Unlike those in alcohols, the -OH group in phenols are supported by a benzene ring that, through +R effect, provides greater electron density in the O atom. As a result, the oxygen atoms in phenols are more capable of stronger intermolecular hydrogen bonding with each other than alcohols, whose OH group is supported by alkyl group (-R effect). This, phenols have higher BP.

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Harsh Sharma 2 years, 10 months ago

Loda bc

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ANSWER

[Cr(NH³)6]³±

Posted by Ananya Kasaudhan 2 years, 10 months ago

CBSE > Class 12 > Chemistry

1 answers

Yashi Kushwaha 2 years, 8 months ago

If you need oxidation number than it is 3 We consider Cr=x NH3 is neutral outside bracket we have 3 X+(0*6)=3 X+0=3 i.e X=3

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Koi mycbse guide ka class 12 physics/chemistry/maths ka sample papers buy kiya h please 🙏 Pdf share kr do

Posted by Rounak Anand 2 years, 10 months ago

CBSE > Class 12 > Chemistry

2 answers

Rounak Anand 2 years, 10 months ago

Muh mein lega lund

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Harsh Sharma 2 years, 10 months ago

Loda bc

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Which is more stable compound in nature

Posted by K. Priyanka_Xi_C_16 2 years, 10 months ago

CBSE > Class 12 > Chemistry

1 answers

Sushma Pandey 2 years, 10 months ago

Ph3C+ is most stable due to presence of three benzene rings which are resonance stabilised.although more compound are stable but this more srable

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Give reasons: (i) Benzoic acid is a stronger acid than acetic acid. (ii) Methanal is more reactive towards nucleophilic addition reaction than ethanal.

Posted by Sazid Sheikh 2 years, 9 months ago

CBSE > Class 12 > Chemistry

1 answers

Preeti Dabral 2 years, 9 months ago

1. Due to greater electronegativity of sp² hybridised carbon to which carboxyl carbon is attached and greater resonance stabilization of carboxylate ion with the benzene ring, benzoic acid is a stronger acid than acetic acid.
2. Methanal is more reactive towards nucleophilic addition reaction than ethanal because carbonyl carbon of methanal is more electrophilic than that of ethanol. Also, due to +I effect of methyl group in ethanal, reactivity of ethanal decreases.

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What is dual cell

Posted by Priu S 2 years, 9 months ago

CBSE > Class 12 > Chemistry

1 answers

Preeti Dabral 2 years, 9 months ago

The dual cell heat exchanger consists of two porous fluid zones, namely a primary zone and an auxiliary zone. The two zones are solved simultaneously and are coupled only through heat transfer.

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Vector sum rules

Posted by Aniket . 2 years, 10 months ago

CBSE > Class 12 > Chemistry

1 answers

Aniket . 2 years, 10 months ago

In physics

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How can be find ethers and alcohol from hydrocarbon

Posted by Shalu Shrivastav 2 years, 10 months ago

CBSE > Class 12 > Chemistry

0 answers

ANSWER

What is iupac name of CH3

Posted by Shaurya Singh 2 years, 10 months ago

CBSE > Class 12 > Chemistry

3 answers

Akshatha E K 2 years, 10 months ago

Methyl

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Ankush Dahiya 2 years, 10 months ago

Methyl group

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Shalu Shrivastav 2 years, 10 months ago

Methyl group

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What mass of ethylene glycol (molar mass 62.0g mol) must be added to 5.50kg of water to lower the freezing point of water from 0 to_10.0 ( kf for water 1.86kgmol)

Posted by Nik Nik 2 years, 10 months ago

CBSE > Class 12 > Chemistry

1 answers

Ankit Kumar Kumar 2 years, 10 months ago

CBSE sample paper

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Although zirconium belongs to 4d transition series and hafnium to 5d transition series even them they show similar physical and chemical properties because

Posted by Ahuja Yadav 2 years, 11 months ago

CBSE > Class 12 > Chemistry

1 answers

Meemansha Srivastava 2 years, 11 months ago

As we go down the group the size of the atoms should increase. This trend is seen till 4d series. In 5d series the electrons fill in the penultimate shell i.e in the d subshell. The sheilding effect by the electrons in the d subshell is less than the attractive force between the electrons in the last subshell and the increasing nuclear charge. Thus the size of the atom reduces (This phenomenon is called as lanthanoid contraction). The expected increase in size of the 5d series is compensated by lanthanoid contraction and hence 4d and 5d series have almost the same size resulting them to have similar physical and chemical properties.

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Which of the following is not currectly matched with its IUPAC name

Posted by Shubham Baba 2 years, 11 months ago

CBSE > Class 12 > Chemistry

1 answers

Kashu Verma 2 years, 10 months ago

Plz tell your question correctly 😃.

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23. In an experiment if 29.6 g Ca(OH)2 in dissolve in water its prepare its aqueous solution of concentration 2M then determine the The volume of the solution?

Posted by Annu Kri 2 years, 11 months ago

CBSE > Class 12 > Chemistry

2 answers

Anjan Karthi 2 years, 11 months ago

Molar mass of Ca(OH)2 = 40 + (1 + 16) × 2 = 40 + 34 = 74 g.// Therefore, Molarity = W/MV. V = W/M × Molarity = 29.6/2 × 74 = 0.2 L = 200 mL.//

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Shubham Baba 2 years, 11 months ago

Which of the following is not correctly matched with its IUPAC name

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ANSWER

Chapter 11 excercise

Posted by Parth Vaishya 03 2 years, 11 months ago

CBSE > Class 12 > Chemistry

1 answers

Anshul Pratap Singh 2 years, 4 months ago

See ncert book 📚

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Intext 2.6

Posted by Jai Vignesh 2 years, 11 months ago

CBSE > Class 12 > Chemistry

1 answers

Kashu Verma 2 years, 10 months ago

Solubility of H2S gas =0.195m 0.195 mole in 1kg of solvent= 1000g 1000/8=55.55moles Therefore, xH2S = 0.195/0.195+55.55=0.0035 Pressure at STP=0.987bar Applying Henry's law, PH2S=KH×XH2S KH=PH2S/XH2S= 0.987/0.0035=282bar...

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How much electricity is required in coulomb for the oxidation of 1 mole of H2O to O2

Posted by Madhwan Pratap 2 years, 9 months ago

CBSE > Class 12 > Chemistry

1 answers

Preeti Dabral 2 years, 9 months ago

{tex}\mathrm{H}_2 \mathrm{O} \rightarrow 2 \mathrm{H}^{+}+\frac{1}{2} \mathrm{O}_2+2 \mathrm{e}^{-}{/tex}

Oxidation of one mole of water will require 2×96500=1.93×10⁵C.

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Maximum boiling azeotrope

Posted by Farman Malik 2 years, 11 months ago

CBSE > Class 12 > Chemistry

1 answers

Kanhaiya Saraswat 2 years, 11 months ago

Which show large negative deviation are of Maximum boiling Azeotrope

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ANSWER

2CH3CHO Iupac name

Posted by Garima Sharma 2 years, 11 months ago

CBSE > Class 12 > Chemistry

4 answers

Akshatha E K 2 years, 10 months ago

Ethanal

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Shalu Shrivastav 2 years, 10 months ago

Ethanal

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Sachin Gupta 2 years, 11 months ago

Ethanal

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Vishal Kaushik 2 years, 11 months ago

Methyl

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2CH3CHO name

Posted by Garima Sharma 2 years, 11 months ago

CBSE > Class 12 > Chemistry

3 answers

Priyanshu Patel 2 years, 10 months ago

2 acetaldehyde

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Ankush Dahiya 2 years, 10 months ago

Ethanal

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Aniket . 2 years, 10 months ago

2 methal

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(i) In decreasing order of basic strength in aqueous solution : C_{2}*H_{5}*N*H_{2} ,(C 2 H 5 ) 2 NH, (C_{2}*H_{5}) 3 N

Posted by Falak Vaishya 2 years, 11 months ago

CBSE > Class 12 > Chemistry

1 answers

Anjan Karthi 2 years, 11 months ago

(C2H5)2NH greater than (C2H5)3N greater than C2H5NH2.

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Difference between rate law and rate constant

Posted by R.Sasi Kumar 2 years, 11 months ago

CBSE > Class 12 > Chemistry

2 answers

Deeksha Yadav 2 years, 11 months ago

n is order of reaction

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Deeksha Yadav 2 years, 11 months ago

R=kA ki power n K =R/A ki power n

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ANSWER

Give a best topic for investigatory file..?

Posted by Kashish Rathore 2 years, 11 months ago

CBSE > Class 12 > Chemistry

1 answers

Chinu Rana 2 years, 11 months ago

Galvanic cell

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Stabilisation of +2 oxidation state

Posted by Avaneesh Rao 2 years, 9 months ago

CBSE > Class 12 > Chemistry

1 answers

Preeti Dabral 2 years, 9 months ago

The relative stability of the +2 oxidation state increases on moving from top to bottom. This is because on moving from top to bottom, it becomes more and more difficult to remove the third electron from the d-orbital.

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Kisi abhikriya Ki Ardh aayu sandrata ki Ghan Hoti Hai To abhikriya Ki Kothi bataiye

Posted by Rajesh Patel Rajesh 2 years, 11 months ago

CBSE > Class 12 > Chemistry

0 answers

ANSWER

What is the formula of E.A.N

Posted by Ashish Yadav 2 years, 11 months ago

CBSE > Class 12 > Chemistry

3 answers

Naman Sharma 2 years, 11 months ago

EAN = atomic number - oxidation state × 2 coordination number

2Thank You

Mili Singh 2 years, 11 months ago

Effective Atomic Number

3Thank You

Anmol Tomar 2 years, 11 months ago

Jshshf

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ANSWER

6gm of urea and 9gm of glucose are dissolved in in 300 gm of water find the boiling point of solution

Posted by Mukti Bhatti 2 years, 9 months ago

CBSE > Class 12 > Chemistry

1 answers

Preeti Dabral 2 years, 9 months ago

The boiling point of the solution is 273.41 k

GIVEN

Weight of urea = 6 grams

weight of Glucose = 9 grams.

Weight of water = 300 grams

TO FIND

The boiling point of the solution.

SoOLUTION

We can simply solve the given problem as follows-

To calculate the boiling point of the solution, we will apply the following formula -

∆Tₒ = Kb× b × i (eq 1)

Where,

∆Tₒ = boiling point elevation

Kb = ebullioscopic constant of the solvent ( kb = o.515 kg/mol)

b = molality of the solute

i = van't Hoff factor of solute ( since urea and glucose are non-ionic compounds, so, i= 1)

We know that,

Boiling point elevation is defined as :

ΔTₒ = T₁ - T ........(eq2)

where,

T₁ = boiling point of the solution

T = boiling point of the solvent (T = 273.15 k of water)

Now,

{tex}\begin{aligned} & \text { number of moles of urea }=\frac{\text { given weight of urea }}{\text { molar mass of urea }} \\ & = \\ & \frac{6}{60}=0.1 \text { moles } \\ & \text { number of moles of glucose }=\frac{\text { given weight of glucose }}{\text { molar mass of glucose }} \\ & =\frac{9}{180}=0.05 \text { moles } \\ & \text { Total moles of solute }=0.1+0.05=0.15 \text { moles } \\ & \text { molality of solute }(b)=\frac{\text { moles of solute }}{\text { mass of solvent in } \mathrm{kg}} \\ & b=\frac{0.15 \times 1000}{300} \\ & b=0.5 \mathrm{M} \end{aligned}{/tex}

putting the values in ( eq 1) we have

ΔTₒ = 0.512 × 0.5 × 1

ΔTₒ = 0.26 k

Now, putting the value of ΔTₒ in (eq 2)

ΔTₒ = T₁ - T

0.26 = T₁ - 273.15

T₁ = 273.15 + 0.26

T₁ = 273.41 k

Hence, The boiling point of the solution is 273.41 k

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Explain postulates of valency bond theory of complex compounds and explain the following molecules coordination compound by valenc bond theory on the hybridization 1 and second inner and outer orbital and paramagnetism low spin and high spin