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ng to Bronsted-Lowry concept, acid is a substance which donates hydrogen ion and base is a substance which accepts hydrogen ion.                          Here HA is the Bronsted acid and Z is the Bronsted base. Moreover only when we observe the reaction equation we can tell which species is Bronsted acid and which one is the Bronsted base. (Here accepts a proton; hence Bronsted base) (Here the same donates a proton; hence Bronsted acid)According to LEWIS concept acid, it is a substance which accepts a pair of electrons (electrophilic- electron attracting) and base is a substance which donates those pair of electrons in other words a NUCLEOPHILE. \Lewis BASES have LONE pair of electrons. Hence we can very easily identify the Lewis acids and bases.

onal losses are not CONSIDERED and no energy is lost during the reversible process. So, the WORK done BECOMES maximum in the reversible process.W.k.t, In reversible process, Work done = P.dvHere, Pressure = function of volumedv = Change in volumeIf the process is not reversible, then, we will consider "work done" by the SURROUNDING particles on the system. Hence, the "work done" by the surrounding is removed from the work done by system. In IRREVERSIBLE process, work done = P.dv - "work done" by surrounding. Thus, the "reversible work done" is always "more than irreversible" work done. "

is POSITIVE, the REACTION is non-spontaneous."

e reaction, Given,We have to Calculate the TEMPERATURE at which the becomes ZERO, so put \DELTA G\QUAD =\quad 0W.K.T. 0 = 467.9 - T(0.56)T = 835.5 (at which the becomes zero)Above this temperature T = 835.5, becomes positive and so the direction of reaction is reversed."

r blocks of elements in the periodic table are as follows,s BLOCK elements  Electronic configuration:  where n=2- 7General characteristics:Melting point and boiling point are low and are soft metals.High electropositive and low ionisation enthalpies.Strong reducing agents.Good conductor of “electricity and heat”.p block elements  Electronic configuration: General characteristics:TOP to bottom, metallic character increases within a group.Left to RIGHT, increase in “non-metallic character” along the period and form covalent COMPOUNDS.Ionisation enthalpies are higher than the s block elements. d block elements  The configuration of d-block elements is (outer shell) where n=4 to 7General characteristics:Good conductor of electricity and heat.Ionisation enthalpy LIES between s and p block.Ionic and also covalent compounds formed.Oxidation states are variable.f block elements  Electronic configuration:  General characteristics:Heavy metals.High melting point and boiling point.Oxidation states are variable.Coloured compounds.

rs to change in enthalpy or total heat content of a system. Mathematically enthalpy can be expressed as: Total heat content of a system (H) = [internal energy of the system + (pressure X volume) ]                                                         H =  E + PV This state function H depends on mass of the reactants and the PHYSICAL STATES of both the reactants and products. Since, ΔH depends on the physical states of the reactants and products, they must be STATED.

enomenon is CALLED CHEMICAL ADSORPTION or CHEMISORPTION

omposition of any carbonate salt depends upon the ease with which the base can attract and the stability of the salt. In general, if the base is a strong one it attracts the acidic very EASILY whereas the weak base cannot attract the acidic oxide that easily. Thus, NaOH attracts forming more STABLE salt. More stable the salt, more is the ENERGY needed for its decomposition. This accounts for the fact that decomposes at a higher temperature. If we take the case of , it is a product of the weak base LiOH and weak acidic acid. Since, weak acid cannot attract easily. As such the salt formed is not stable. Thus, it decomposes at a lower temperature indicating that less energy is enough for its decomposition to lithium oxide and carbon dioxide. Further the small size of the lithium ion facilitates the polarisation of ELECTRON CLOUD of the oxygen atom to which it is attached. Thus, Li-O bond becomes stronger and C-O bond becomes weaker. Thus lithium carbonate decomposes as -

tains 99% of Nitrogen and Oxygen. Given, the STANDARD FREE energy of formation of NO is 86.7 . These gases at sea level "do not react" with each other and form Nitric acid. But they "combine" to form the nitric oxide (NO) at temperature above . It is then OXIDIZED by the ozone to Nitrogen dioxide. Nitrogen dioxide is toxic to LIVING tissues, and produce acid rain and photochemical smog.

um (Be) is the element belongs to second  group in the periodic table. It is amphoteric and REACTS with acid and bases and is invariably DIVALENT. Its oxide i.e., Beryllium Oxide DISSOLVES in the excess of Sodium HYDROXIDE (NaOH) and gives sodium berrylate and WATER.       The dipositive ion of Beryllium Oxide has a soluble Noble gas core and also

ole moment" is a measure of the "SEPARATION" of "two electric CHARGES"" that are opposite. Moments of dipole are a "vector quantity". The magnitude corresponds to the charge multiplied by the distance between the chare and the DIRECTION from negative to positive charge.Percentage ionic character is calculated as:FORMULA used to calculate dipole moment:"

st in the EARLIER days had so much confusion in the properties of LIGHT, whether it has wave or PARTICLE. Light is an electromagnetic wave and is transversal in nature.      To verify the light’s wave nature, Thomas Young conducted experiments BASED on “diffraction and interference”. He conducted the SINGLE slit and double slit experiments. “Young’s double slit experiment”  put forward strong evidence to the wave nature of light.

and ethyne both of them are saturated hydrocarbons. They can decolourise POTASSIUM tetraoxomaganate and also Bromine water. Ethyne reacts with insoluble salts and gives certain reactions. The reagents which distinguish the ethane and ethyne are  ,a)AMMONIACAL silver nitrate  which is a Tollen’s reagent:              Ethyne reacts with “AMMONICAL silver nitrate” and gives the desilver ACETYLIDE (white precipitate), ethene does not reacts with the Tollens reagent. b)  Solution of “Ammoniacal CUPROUS chloride” is also one of the reagents to distinguish between the ethane and ethyne.

rmine: The energy of pulsed radiation source  Given Data: Duration= 2 ns = NUMBER of emitted photons = Formulas to be used: Energy = Where N = number of emitted photons during the pulse source h = Planck’s CONSTANT = = frequency of the radiation sourceFrequency of source = Calculation: Step 1: FIND frequency of source   Step 2: Substituting  N= h =          In the energy formula, we get ,Energy =

hydroxide is used to identify the BASIC cation. Sodium hydroxide and GALLIUM chloride are IONIC compounds. When aqueous solutions of these TWO compounds are mixed and if a precipitate is formed it means mutual ion exchange has taken place. If this insoluble substance dissolves on further addition of sodium hydroxide, it means a soluble complex is formed.  insoluble soluble

chemical formula for HEAVY WATER  and it is called deuterium oxide. is the chemical formula for ordinary water. Heavy water has its dielectric constant lower than that of ordinary water. This makes ionic compounds less soluble in heavy water. Hence heavy water when consumed, reduces the rate of REACTIONS occurring in human beings, plants and ANIMALS and EVENTUALLY produces harmful effects. Thus, heavy water cannot be used for drinking purposes.

ssibility factor;OrIf VOLUME of molecule is NEGLIGIBLE i.e., B is negligible VANDER Waal's equation becomes OROR"

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saignes’s EXTRACT is usually used for testing any organic compound to find out if the compound contains any halogens or nitrogen or sulphur.  In TAP WATER, there are some chloride ions present. So, if we USE it to prepare the extract, then whatever organic compound we test using the extract, it will always show the presence of chlorine even if the organic compound does not have any halogen in it.  Hence the LASSAIGNE’s extract should be prepared using distilled water and not tap water.

l bromide is FORMED VIA anti m rule.

H of a SOLUTION" is the "NEGATIVE LOGARITHM" of the "hydrogen ion concentration". The pH may be represented "mathematically" with the "FOLLOWING equation". From the GIVEN, The hydronium ion concentration "

rmine: The concentration of at the equilibrium stage when being placed in a flask at  a pressure of 4.0 atm. Given Data: The equilibrium REACTION isInitial pressure of is 4.0 atm Kp, the equilibrium constant, depends on partial PRESSURES exerted by the gaseous components in the given reaction. Kp = 0.04 atm Formulas to be used: Law of chemical equilibrium: Kp is equal to the ratio of the product of  partial pressures of the PRODUCTS of the given reaction, each being raised to the power of their corresponding coefficients to the product of the partial pressures of the reactants, each being raised to the power of their corresponding coefficients. Calculation: Step 1: Diagnose the values to be assigned in the law of chemical equilibrium Initial concentration of = 4.0 atm Initial concentration of = 0 atm Initial concentration of = 0 atm Let the pressure of at equilibrium = p atm So, the pressure of at equilibrium = p atm The pressure of at equilibrium = 4.0-p atm Step 2: Substitute the values obtained in the law of chemical equilibrium Step 3: Using the FORMULA for quadratic equations, we get By taking the positive VALUE alone,  We get p =0.76/2 =0.38 Hence at equilibrium, the pressure of = 4-p-4-0.38 = 3.62 atm

py:It is DEFINED as the "sum" of "internal energy" and "product" of "pressure and VOLUME".Relation between internal energy and enthalpy is ."Standard enthalpy of formation":The "enthalpy change" when "one mole" of a "substance" in "standard state" is formed from its "CONSTITUENT element" in their standard stateFrom the given,The "bond dissociation energy" of = 104 kcalThe "bond dissociation energy" of = 58 kcalThe "bond dissociation energy" of HCl = 103 kcalThe given CHEMICAL reaction is as follows."

ven reaction is as follows The oxidation half reaction is as follows Let's balance the electrons Balance the charges by ADDING Balance the OXYGEN atoms by adding molecules ............(i) The reduction half EQUATION The oxidation number is BALANCED by adding ONE electron as .........(ii) The balanced chemical equation can be obtained by adding equation (i) and (ii) "

ntral atom “B”  in undergoes hybridization. Therefore, the shape of the molecule is planar. It has vacant 2p orbital and also F atom has three LONE pair of electrons. In bond is formed by overlapping of the empty orbital of boron atoms and one 2p - orbital of fluorine.  In, the central atom boron undergoes hybridization. Therefore, it is a tetrahedral molecule.In, they do not have vacant orbital to ACCEPTS the electrons from the fluorine atoms.And it have pure single bond.Hence double bonds are SHORTER than single bonds, therefore, B -F bond LENGTH in is shorter (130 pm) than B-F bond length (143 pm) in ."

Write the reaction along with oxidation number of each element that is present in the reactants as WELL as the products of the reaction. Step 2: Notice that the oxidation number of potassium (K) is 0 in the reactants but it is +1 in the products. So, there is an increase in the oxidation number of potassium during the chemical reaction. Hence it is evident that potassium is oxidized to potassium fluoride. Step 3: Notice that the oxidation number of fluorine(F) is 0 in the reactants but it is -1 in the products. So, there is a decrease in the oxidation number of fluorine during the chemical reaction. Hence it is evident that is reduced to KF. THUS, it is proved that the given reaction is a REDOX reaction .

compound named “Ethyl Mercaptan” contains sulphur and hence it does produce a very foul odour like that of rotten cabbages. This compound gets added in the LPG in smalll quantities when the LPG gets out of the cylinder through the MAIN storage terminals.  The smell that follows because the LPG coming out makes us detect a leakage.  (b) There are two important steps to be taken when the leakage of LPG is detected (i) Open all the windows and the doors at the house – This is done to let air from the atmosphere circulate in the house making the LPG gas move out of the house along with air. Hence there would be no harmful effects. (ii) Stop operating any electrical SWITCHES – This is done because when a switch is pressed , a SLIGHT FIRE SPARK pops up. This spark would be more than enough d to burst a house that is having LPG gas mixed with the air inside the house.  "

ling point of any liquid is defined as the point at which the liquid’s vapor pressure becomes so HIGH such that a constant flow of vapour keeps coming out from the liquid. Now considering the boiling point of water, when the atmospheric pressure increases, the vapour pressure of the water ALSO increases. This IMPLIES, that the hotness of water is directly proportional to the atmospheric pressure.  Thus, we can say that the boiling point of water at sea level WOULD be greater than that MEASURED at any elevation above sea level because when the elevation is less, the atmospheric pressure is high.

is the "smallest part" of an "element" that undergoes a "chemical reaction". Mass of atom can be denoted by two WAYS. A mass of a single atom which is measured in ATOMIC mass unit. Atomic number of element indicates the "number of PROTONS" and "electrons" are present in the element. Depending upon the atomic number electrons are arranged in pair or unpaired. Therefore, the following STATEMENT is wrong. “EVERY atom" with "even atomic number" has all "paired electrons”."

rm "significant figures" REFERS to the "number" of "important single digits" (From 0 to 9) in the expression coefficient in scientific notation. The "number of significant figures" in an "expression"" shows the "confidence or accuracy" with which a PERSON states a "quantity".The FOLLOWING three rules are used to determine the number of significant numbers in a number:  · Non-zero numbers are always significant  · Any zeros between two significant numbers are significant.· A "FINAL zero" or "trailing zeros" in the "decimal portion" are only important. Examples:  0.900 or 0.928000, the zeros are significant.(i) (ii) "

All the alkali metals are paramagnetic because of the presence of one valence electron in the valence SHELL. The alkali METAL cations i.e. Li+, Na+, K+, RB+ and Cs+ all are DIAMAGNETIC because of absence of unpaired electrons.Hope it helps you:)Please mark me brainliest:)

borate is also called as BORAX. It is one of the important forms of boron compound. Sodium tetraborate and disodium tetraborate are salt forms of boron.Borax are white COLOURED crystals which are readily dissolved in water.On heating strongly, borax loses "water of CRYSTALLIZATION" to form colourless, "transparent glass" like "bead" made up of "sodium metaborate" and "BORIC anhydride."The reaction is as follows. "

ven two half-cell reactions are as follows ForForFrom the above "two half-cell" reactions, STANDARD ELECTRODE potential VALUES for "two half-cell" reactions indicate that aluminium has high TENDENCY to form trivalent form, i.e., . But it is not applicable to because it is UNSTABLE ion and it is strong oxidizing agent. The stable form of this ion is Therefore, aluminium easily form trivalent ion and more electropositive than Thallium."

the "presence of SUNLIGHT" methyl benzene TREATED with chlorine to form chlorophenyl methane. The reaction is as follows.(ii) In the presence of methyl benzene treated with chlorine to form ortho and para chloro TOLUENE. The reaction is as follows.(iii) In the presence of and methyl benzene undergoes oxidation to "form BENZOIC acid". The reaction is given below."

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orax solution is acidified the FOLLOWING reaction takes placeBeing a WEAK acid Borax hydrolyzed in solution and is ALKALINE in nature "

I) hydroxide ,  is also called as hydrated iron OXIDE or yellow iron oxide. It is odourless and is insoluble at pH 7. We can obtain Iron(III) hydroxide by reacting ferric chloride with sodium hydroxide:                    The precipitate of Ferric hydroxide is not obtained at pH=2. Because Iron(III) hydroxide (Fe(OH)3 dissolves only in the STRONG acidic medium.

oelectronic species are those elements which have same or equal number of electrons or valence electrons(i) is ISOELECTRONIC with which has 10 electrons in its shell(ii) Ar is isoelectronic with   and which has 18 electrons in its shell(iii) is isoelectronic with Ne, ANDWHICH has 10 electrons in its shell(iv) is isoelectronic WITHWHICH has 36 electrons in its shell"

mical FORMULA for washing SODA is GIVEN as . When exposed to air the water molecules gets absorbed by the sunlight. After absorption of the water molecules, the white POWDER results. The white powder is . This process of losing water molecules when "exposed to air" is CALLED "efflorescence".