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Why Amorphous solids are called as pseudo solids?

Posted by Poleboina Rishitha 3 years, 5 months ago

5 answers

Vaishali ..... 3 years, 5 months ago

Glass is considered to be super cooled liquid or pseudo solids because it shows some of the characteristics of liquids though it is an amorphous solid. For example , it is slightly thicker at the bottom . This can be possible only if it has flown like liquid , though very slowly . Hope it will helpful to u Thanku

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Poleboina Rishitha 3 years, 5 months ago

Examples plz

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Priya Rao 3 years, 5 months ago

Because they have tendency to flow slowly

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Anchal Shukla 3 years, 5 months ago

Amorphous solids are also called super cooled liquids like glass. We can see that in ancient palaces glass of windows as example of it

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Studious Fellow 3 years, 5 months ago

Like liquids amorphous solids have tendency to flow but very slowly so therefore they are called pseudo solids

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In an S N1 reaction of alkyl halide on chiral center there is .....

Posted by Muskan Saini 3 years, 5 months ago

CBSE > Class 12 > Chemistry

2 answers

Muskan Saini 3 years, 5 months ago

Tq dear

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__I.Am.Shyam. Jaat?__ 3 years, 5 months ago

Inversion more than retention leading to partial racemizatiom.

2Thank You

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Why aluminium nitrite is an covalent solid

Posted by Tanisha Sodani 3 years, 5 months ago

CBSE > Class 12 > Chemistry

0 answers

ANSWER

फेहलिंग अभिकर्मक किसे कहते है

Posted by Puspa Patail 3 years, 5 months ago

CBSE > Class 12 > Chemistry

2 answers

Mewalal Dewangan 3 years, 5 months ago

fehling abhikaramk

4Thank You

Bawan Netam 3 years, 5 months ago

फेहलिंग अभिकर्मक क्या है?

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How does GCV differ from NCV? A sample of coal was analyzed as follows, Weight of coal burnt 1.029 g, weight of water taken in calorimeter is 2200g, Water Equivalent of apparatus is 570 g, Rise in temperature is 2.30C. Cooling correction is 0.047 o C Fuse wire correction is 3.8 cal and acid correction is 62.6 cal. Cotton thread correction is 1.6 Cal. Calculate GCV and NCV of coal if it contains 0.5% Hydrogen

Posted by Surbhi Panwar 3 years, 5 months ago

CBSE > Class 12 > Chemistry

0 answers

ANSWER

An optically active compound is (a) 1-bromobutane (b) p-bromobutyric acid (c)2-bromo-2-methylpropane (d)1-bromo-2-methylpropane

Posted by Sony Chauhan 3 years, 5 months ago

CBSE > Class 12 > Chemistry

0 answers

ANSWER

To phenyl 2 chloropropane on treatment with alcohol KOH gives which of the following as major product? (1) 2-phenylpropene (2) 3-phenylpropan (3)1-phenylpropan-2-ol (4)1-phenylpropan-3-ol

Posted by Sony Chauhan 3 years, 5 months ago

CBSE > Class 12 > Chemistry

0 answers

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Assertion the para isomers are high melting as compared to their orthoand meta isomers reason:charge separation is higher in Para isomer.

Posted by Sony Chauhan 3 years, 5 months ago

CBSE > Class 12 > Chemistry

1 answers

Sia ? 3 years, 5 months ago

Please ask question with complete information.

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Assertion: the boiling points of chloride Bromide and iodide ions are considerable higher than those of the hydrocarbons of comparable molecular mass. reason:c-x bond is Polar.

Posted by Sony Chauhan 3 years, 5 months ago

CBSE > Class 12 > Chemistry

1 answers

Sia ? 3 years, 5 months ago

Please ask question with complete information.

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Assertion: Kinkelstein reaction is carried out in presence of acetone. reason: in facilities the forward direction according to Le chatelier's principle by participating by-product.

Posted by Sony Chauhan 3 years, 5 months ago

CBSE > Class 12 > Chemistry

1 answers

Sia ? 3 years, 5 months ago

Please ask question with complete information.

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Assertion: alkyl halides are not prepared by reaction of phenol with Vinyl chloride Reason: carbon oxygen bond in phenols is difficult to break due to partial double bond character.

Posted by Sony Chauhan 3 years, 5 months ago

CBSE > Class 12 > Chemistry

0 answers

ANSWER

Assertion:thionyl chloride is preferred over Phosphorus Chloride for the preparation of alkyl chlorides from alcohols. Reason: Phosphorus chloride does not give pure alkyl halide. (1) both assertion and reason are correct and reason is not the correct explanation of the assertion. (2) both assertion and reason are correct but reason is not the correct explanation of assertion. (3) assertion is correct but reason is incorrect. (4) assertion is incorrect but reason is correct.

Posted by Sony Chauhan 3 years, 5 months ago

CBSE > Class 12 > Chemistry

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For a given alkyl group, the boiling point of alkyl halides follow the order: (1) RL>RBr>RCL> (2) RCL>RBr>RI (3) RI>RCI>RBr (4) RBr>RI>RCL

Posted by Sony Chauhan 3 years, 5 months ago

CBSE > Class 12 > Chemistry

1 answers

Ravi Kumar 3 years, 5 months ago

(1) (RI>RBr>RCL) is correct answer.

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Define order of reaction

Posted by Ambika Shahdeo 3 years, 4 months ago

CBSE > Class 12 > Chemistry

1 answers

Sia ? 3 years, 4 months ago

Order of a chemical reaction can be defined as the sum of power of concentration of reactants in the rate law expression is called the order of that chemical reaction. Reactions can be first order reaction, second order reaction, pseudo first order reaction etc. depends on the concentration of the reactants. Order of a reaction is an experimental value. It means it is an experimentally determined parameter. It can have fractional value as well.

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Assuming that Raoult's Law is followed,what would be the vapour pressure of a solution formed when 40 g of sugar(molecular mass 342) is dissolved in 360 mL of water at 25°C? At 25°C the vapour pressure of water is 20 mm and the density is 1g/mL

Posted by Taranveer Singh 3 years, 5 months ago

CBSE > Class 12 > Chemistry

0 answers

ANSWER

Kia paper cancel honge ?

Posted by Kunal Garg 3 years, 5 months ago

CBSE > Class 12 > Chemistry

3 answers

Devil ? 3 years, 5 months ago

Ho gye n

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Anurag Saral 3 years, 5 months ago

No... obviously...

1Thank You

Bhanu Khumawat 3 years, 5 months ago

No..?

1Thank You

ANSWER

D block elements

Posted by Atriman Shukla 3 years, 5 months ago

CBSE > Class 12 > Chemistry

3 answers

Sia ? 3 years, 5 months ago

2Thank You

Priya Rao 3 years, 5 months ago

Sc,ti,v,cr,mn,fe,co,ni,cu,zn

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Black Panther 3 years, 5 months ago

Sia..

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Assertion: The first layer is mobile in Helmholtz electrical double layer. Reason: The potential difference between the fixed layer and the diffused layer of opposite charges is called zeta potential.

Posted by Anbu Chelvan 3 years, 5 months ago

CBSE > Class 12 > Chemistry

2 answers

Prabhjot Kaur 3 years, 4 months ago

d option) assertion is wrong stament but reason is correct statement

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Prabhjot Kaur 3 years, 4 months ago

d option

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In group 15 elements, there is considerable increase in covalent radius from N to P but small increase from As to Bi. Why?

Posted by Gloria Laloo 3 years, 5 months ago

CBSE > Class 12 > Chemistry

1 answers

Anuradha Patwari 3 years, 6 months ago

Due to inert pair effect

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Write 5 small difference between adsorption and absorption

Posted by Sh G 3 years, 6 months ago

CBSE > Class 12 > Chemistry

1 answers

Rounik Roy 3 years, 6 months ago

See in ncert book

6Thank You

ANSWER

How to differentiate between Friedel crafl alkylation reaction and friedal craft allilation

Posted by Ankit Soni 3 years, 6 months ago

CBSE > Class 12 > Chemistry

3 answers

Bhawana Mishra 3 years, 5 months ago

Alkyl ka reagent - AlCl³ hota hai or acylation ka CH3COCl

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Black Panther 3 years, 6 months ago

Reagent is - an alcl3

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Black Panther 3 years, 6 months ago

Alkyl means - ch3-cocl Allylation means - ch3-cl.

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Knowing the radii of tha cation and anion of an ionic compound how can you predict the structure of the compound ?

Posted by Urvashi Sharma 3 years, 6 months ago

CBSE > Class 12 > Chemistry

3 answers

Taranveer Singh 3 years, 5 months ago

If it is 0.155-0.225 structure is trigonal If it's 0.225-0.414 structure is tetrahedral If it's 0.414-0.732 structure is octahedral 0.731-1.00 structure is BCC

1Thank You

Taranveer Singh 3 years, 5 months ago

After that if it comes: <0.155 structure is linear

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Taranveer Singh 3 years, 5 months ago

Find the radius ratio which is : radius of cation/radius of anion

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Why Mn2O3 is basic and Mn2O7 is acidic

Posted by Noyal Johny 3 years, 6 months ago

CBSE > Class 12 > Chemistry

0 answers

ANSWER

Calorific value of CNG ??

Posted by Diya Singh 3 years, 6 months ago

CBSE > Class 12 > Chemistry

1 answers

Sia ? 3 years, 5 months ago

12500 kcal/kg

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Tery butylmethylether

Posted by Akansha Singh 3 years, 6 months ago

CBSE > Class 12 > Chemistry

1 answers

Diya Singh 3 years, 6 months ago

It is a compound with the structure formula (CH3)3COCH3. It supply oxygen from the ether group for combustion of petrol, thus reduce the formation of peroxy compounds.

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Transition metals except zn,cd,hg are hard and have high melting and boiling point

Posted by Dimpy Agarwal 3 years, 6 months ago

CBSE > Class 12 > Chemistry

1 answers

Divyanka Krishna 3 years, 6 months ago

Zinc, cadmium and Mercury have completely filled d orbital

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What do you mean by Overpotential and overvoltage? Explain

Posted by Hitesh Jindal 3 years, 6 months ago

CBSE > Class 12 > Chemistry

1 answers

Diya Singh 3 years, 6 months ago

Overpotential is typically used to describe the behaviour of one eletrode while electrovoltage is used for the complete cell and includes overpotential from each electrode as well as losses in the electrolyte and other component

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Find molality of 0.5 molar NaNO3 solution, if density of solution is1.2g/ml

Posted by Rohit Bais 3 years, 6 months ago

CBSE > Class 12 > Chemistry

1 answers

Black Panther 3 years, 6 months ago

.44

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( please give me the ans or explanation on them ) Halogen acid molecular sites HF, HCl , HBr and HI . Now, among the four halogen acid why anti markovnikov rule is shown only by HBr ?

Posted by Arnab H. 3 years, 6 months ago

CBSE > Class 12 > Chemistry

1 answers

Prachi Agarwal 3 years, 6 months ago

The bond strength order of halogen acid is . HF and HCl have high bond strength and polarity, so homolytic cleavage does not occur easily. In HBr and HI, homolytic clevage occurs readily to produce bromine and iodine free radicals. However, iodine radicals undergo coupling reaction with similar iodine radical to form iodine molecule.
As a result radicals are not available for addition on alkenes. Thus, only HBr can provide free radical for addition to alkenes. Thus ,this rule is only applicable to HBr

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How will you prepare fluoroethane from an alcohol

Posted by Neil Modi 3 years, 6 months ago

CBSE > Class 12 > Chemistry