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correct option is 3 that is F centres

a ..The SI unit for Entropy (S) isJoulesper Kelvin (J/K).

Point defects are where an atom is missing or is in an irregular place in the lattice structure.

Point defects include self interstitial atoms, interstitial impurity atoms, substitutional atoms and vacancies. An example of interstitial impurity atoms is the carbon atoms that are added to iron to make steel.

AFrenkel defectorFrenkeldisorder is a type ofpoint defectin acrystal lattice.

Thedefectforms when an atom or smaller ion (usually cation) leaves its place in the lattice, creating a vacancy, and becomes an interstitial by lodging in a nearby location

metal deficiency defect decreases the density of solid

When some constituent particles (atoms or molecules) occupy an interstitial site, the crystal is said to have interstitial defect. This point defect increases the density of the substance.

Limestoneis a carbonate sedimentary rock that is often composed of the skeletal fragments of marine organisms such as coral, foraminifera, and molluscs. Its major materials are the minerals calcite and aragonite, which are different crystal forms of calcium carbonate (CaCO3).

the monomer unit of Teflon isTetrafluoroethylene, which isC2F4.

Zinc, being a metal can be beaten into thin sheets.

Option 1. Because, for rusting, moisture is an essential factor.

Hydrogen fuelis a zero-emissionfuelwhen burned with oxygen. It can beusedin electrochemical cells or internal combustion engines to power vehicles or electric devices. ... The energy released enableshydrogento act as afuel. In an electrochemical cell, that energy can beusedwith relatively high efficiency.

2)It is not as easy as it appears to be. Combination of hydrogen and oxygen atoms is accompanied by release of tremendous amount of energy.

This chemical reaction, when occurs, produces a large amount of energy, which may amount to a full scale, deadly explosion. This is exactly what happened in the Hindenburg Disaster in 1937.

In order to manufacture water to cater to the needs of such a large population on the planet, the laboratories and the facilities required to contain such great and spontaneous emission of energy would betoo expensive to be practically and economically viable.

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Oresare solid material from which a pure metal can be obtained. The process of removal of unwanted material from theoreis known asconcentrationor dressing or benefaction ofores. ... The only useful material isore. Gangue is removed from the mineral for the extraction of theore.

Concentration Definition:

The process of removal of the gangue from Ore is known as Concentration or Dressing or Benefaction. There are numerous methods of concentration and the methods are chosen based on the properties of the ore.

Hydraulic Washing:

This method concentrates the ore by passing it through an upward stream of water whereby all the lighter particles of gangue are separated from the heavier metal ore. This is a type of gravity separation.

Magnetic Separation:

This involves the use of magnetic properties of either the ore or the gangue to separate them. The ore is first ground to fine pieces and then passed on a conveyor belt passing over a magnetic roller. The magnetic ore remains on the belt and the gangue falls off the belt.

Froth Flotation Method:

This method is mainly used to remove gangue from sulfide ores. The ore is powdered and a suspension is created inwater. To this are added, Collectors and Froth Stabilizers. Collectors (pine oils, fatty acids etc) increase the non-wettability of the metal part of the ore and allows it to form a froth. Froth Stabilizers (cresols, aniline etc) sustain the froth. The oil wets the metal and the water wets the gangue. Paddles and air constantly stir up the suspension to create the froth. This frothy metal is skimmed off the top and dried, to recover the metal.

Leaching:

Leaching is used when the ore is soluble in a solvent. The powdered ore is dissolved in a chemical, usuallya strongsolutionof NaOH. The chemical solution dissolves the metal in the ore and it can be extracted and separated from the gangue by extracting the chemical solution. Extraction of the Aluminium metal from Bauxite ore is done using this process.

Most of the large structures you see around you today have metallurgy to thank for their existence. What we learned now is just the beginning in the extraction of metals.

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a. Metal carbonate ore is heated under the absence of oxygen- calcination process. From this we obtain their oxide which is then reduced by coke. thus pure metal is obtainedb. Roasting of copper(l) sulphide Reduction kf copper(l) oxide with copper(l) sulphide- electrolyte refining.

bisnu kya question ka whole paper ap send kroge

example

Mineralsare naturally occurring inorganic solidswith acrystalline structure and a definite range of chemical formula.Oresare concentrations ofmineralsin rock that are high enough to be economically extracted for use.

Ductilityandmalleability are propertiesof metalsthat showspecific characteristics.Itis theductilityandmalleability property thathelps the metals to deform.Ductilityis said to be thepropertyof a material to stretch without getting damaged. Metals havingductile property canbe stretched into wires.Feb

I think so acceleration

This observation show the property that particles of matter have gap between them

The particle of matter of liquid have space between them

A diver can do so because water is made up of particles. Moreover, when the diver cut the water it shows that there are intermolecular spaces between the particles of matter present in water and these particles of matter attract each other.

because in water the attractive force between the particles is less

because in water the attractive force between the particles is less

this shows that the particles of water have enough space between them

intermolecular space between particles of liquid is more

Hybridization with mores−character stabilizes carbanion.s−orbtial lies closer to the nucleus thanp. Thus,sp > sp2> sp3

A diver is able to cut through water in a swimming pool because being a liquid it has weak inter mlecules force of attraction between the molecules

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The splitting of the d orbitals in an octahedral field takes palce in such a way that dx2y2, dz2experience a rise in energy and form the eg level, while dxy, dyzand dzxexperience a fall in energy and form the t2glevel.

Micro organism plays vital in our daily life

1.Lactic acid bacteria converts the milk into curd.

2. Cows eat many plants and grass they are digest by the micro organisms called asachlorohudria.

3.Algae are used for making biogas.

4. Acetobacter acetic produce the acetic acid.

5. Fungus are the cause of citric acid in lemon.

a) Zinc oxide is an example of non stoichiometric defect under the category metal excess defect (excess cations occupying the interstitial site). In ZnO, Zn2+ions occupy the interstitial sites and electrons are trapped in the interstitial sites for the neutralization. Crystals that shows such type of defects are generally colored.

Zinc oxide is white in color but on heating it turns into yellow because on heating it loses oxygen reversibly at high temperature.

The reaction is as under:-

ZnO → Zn2++ 1/2 O2+ 2e-

b) Schottkey defect is the vacancy found in the crystal lattice of ionic compounds due to size difference in cations.

Here, we know that Ca is a divalent cation and remains as Ca+2while silver is a univalent cation and remains as Ag+.

So, when CaCl2is added to AgCl, then one Ca+2ion will replace two Ag+ions which will create a vacancy in place of one Ag+ion and so there will be the Schottkey defect in the compound.

Na2CO3 (sodium carbonate) is a base.HCl (hydrochloric acid) is an acid.NaOH (sodium hydroxide) is also a base.

When we react sodium carbonate with hydrochloric acid they will react and neutralize each other, in a neutralization reaction.2HCl + Na2CO3 --> 2NaCl + H2O + CO2

But on the other hand two bases will not react with each other. Thus we can distinguish between HCl and NaOH as one will react will Na2CO3 and one won't.

Na2CO3 (sodium carbonate) is a base.HCl (hydrochloric acid) is an acid.NaOH (sodium hydroxide) is also a base.

When we react sodium carbonate with hydrochloric acid they will react and neutralize each other, in a neutralization reaction.2HCl + Na2CO3 --> 2NaCl + H2O + CO2But on the other hand two bases will not react with each other. Thus we can distinguish between HCl and NaOH as one will react will Na2CO3 and one won't.

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On moving fromleft to rightin aperiod, the number ofvalenceelectrons decreases from 8 to 1.

b) decreases is correct

a)ethanoic acid functional group= -OOHb)and c)In order to identify presence of carboxylic acids, they should treat with bases like Sodium hydroxide (NaOH).Formation of salt (sodium acetate) and water confirms the presence of acids.CH₃COOH + NaOH → CH₃COONa + H₂ONot only with bases but carbonates and bicarbonates also forms sodium acetate.Reaction of ethanoic acid with ethyl alcohol produces ethyl acetate. Formation of ethyl acetate (ester) indicates sweet smell. CH₃COOH + C₂H₅OH →CH₃COOC₂H₅ + H₂O

A lichen is not a single organism. Rather, it is a symbiosis between different organisms - a fungus and an alga or cyanobacterium. Cyanobacteria are sometimes still referred to as 'blue-green algae', though they are quite distinct from the algae. The non-fungal partner contains chlorophyll and is called the photobiont.

It is a type of microbes which feed on bacteria

Amorphous solids are isotropic - meaning while measuring a particular property of the material, you'll get the same result no matter from which side or length of the material you take your measurements from. For example the electrical resistance of a glass piece would be the same through out its body - inside the bulk, surface, through the length or through the breadth. However, since Crystalline solids have a long range order, their arrangement of particles in different directions would be different and hence they would behave as an-isotropic materials.

Crystalline solids are more rigid. In fact, if you come across a very old glass you'll observe that it is bulkier downwards. This is because glass particles are very slowly flowing downwards under the effect of gravity. This would not happen in a crystal.

.Crystal field theory (CFT) describes the breaking of orbital degeneracy intransition metal complexesdue to the presence ofligands..CFT qualitatively describes the strength of the metal-ligand bonds.Based on the strength of the metal-ligand bonds, the energy of the system is altered. .This may lead to a change inmagnetic propertiesas well ascolor.

Interstitials defects are a variety of crystallographic defects where atoms assume a normally unoccupied site in the crystal structure. In interstitial defects three or more atoms may share one lattice site, thereby increasing its total energy.

Robert Hooke discovered the cells. He saw that the cork resembled the structure of a honeycomb consisting of many little compartments. Cork is a substance which comes from the bark of a tree. This was in the year 1665 when Hooke made this chance observation through a self-designed microscope. Robert Hooke called these boxes cells. In this way he discovered the cells.

i)XeOF4

In order to be able to determine the molecular geometry of xenon oxytetrafluoride,

XeOF4, you need to start by drawing its Lewis structure.

To find the number of valence electron you get in one molecule of xenon oxytetrafluoride, add the number of valence electrons of each individual atom that makes up the molecule.

So, xenon oxytetrafluoride will have a total of

42 valence electrons 8 valence electrons are coming from the xenon atom 6 valence electrons are coming from the oxygen atom 7 valence electrons from each of the four fluorine atoms.

Now, xenon will be the central atom. It will bond with the oxygen atom via a double bond. This will ensure that oxygen has a complete octet.

The xenon atom will bond with the four fluorine atoms via four single bonds, which will ensure that each of the four fluorine atoms gets a complete octet. Afterwards the xenon atom will make double bond with oxygen atom to fulfill its octet. The remaining two electrons will remain as a lone pair.

Typically, N–N bonds are similar in length to that inhydrazine(145 pm). Dinitrogen trioxide, however, has an unusually long N–N bond at 186 pm. Some other nitrogen oxides do also possess long N–N bonds, including dinitrogen tetroxide (175 pm). The N2O3molecule is planar and exhibits Cs symmetry. The dimensions displayed below come from microwave spectroscopy of low-temperature, gaseous N2O3

Based on VSEPR Theory (Valence Shell Electron Pair Repulsion Theory) the electron clouds on atoms and lone pairs of electrons around the O will repel each other. As a result they will be pushed apart giving theOF2molecule a bentgeometryorshape.

6:5 is the correct answer or your answer is d)

d is the correct answer

Not able to see the pictures.

MW of glucose 180.2

The mass of 1

mol= 180.2 g + 1000g solvent 1180.2 g

The mass o 0.2 mol = 180 x 0.2 = 36 g

the mass of solution of 0.2 molality = 1036 g

We Will have 0.2 molality in 10036 g of the given solution

36 g/ 180.2 = 0.2 mol

And 1000 g of solvent = 0.2 mol/1 kg

∆n = 3-2 = 1 , R = 0.082

so, Kp = Kc (RT)^(∆n) = 375×10^-6 × (0.082×500) => Kp = 375×10^-6 × (41.15) = 0.0154

when the reaction is reversed , the equilibrium constant becomes 1/k

and when the reaction is then halved , the equilibrium constant becomes (1/k)^(1/2)

so, the answer is new eq. constant = 1/√k

A hydrogen bond is a type of attractive (dipole-dipole) interaction between an electronegativeatomand ahydrogenatombondedto another electronegative atom. This bond always involves a hydrogen atom.Hydrogen bondscan occur betweenmoleculesor within parts of a single molecule.

A hydrogen bond tends to be stronger thanvan der Waals forces, but weaker thancovalent bondsorionic bonds. It is about 1/20th (5%) the strength of the covalent bond formed between O-H. However, even this weak bond is strong enough to withstand slight temperature fluctuation.