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eve arranged the elements on the BASIS of their ATOMIC masses and so its close to modern PERIODIC table. He SAID that the periodic properties of elements are the results of their atomic masses whereas the modern table STATES that the periodic properties of elements are the results of their atomic numbers

is one of the state of matter like solid, liquid, gas.it is FORTH fundamental stat. PLAZMA CONDITION is creat by heating matter under ELECTROMAGNETIC condition. when it HEATED positively charged ions and negatively charged electrons produce.

it'sA – R B – Q C – SD - P

series in order of the standard electrode potentials.  the NEGATIVE potentials are PLACED at the top while positives are placed below n hydrogen is placed in the middle . more negative , more it is the reducing agent . this series is CALLED electrochemical series.

on rods forheating LIQUIDS are made up of METALLIC SUBSTANCES as metals are GOOD CONDUCTERS of heat and therefore they can conduct heat through them to liquids.

umbum(PB)sorrry i don't KNOW for TIN.

d in TAMRIND is TARTARIC ACID.

othing but the process of purifying the LIQUID by heating and then by COOLING. this process is CALLED DISTILLATION

is the ANSWER

acids are compounds which are organic and are acidic in NATURE. We can't say a compound is organic just because it is produced in an ORGANISM. HCl is produced in our body but it is not an organic compound. To be organic, there should be COVALENTLY BONDED carbon atoms in it. There is no covalently bonded carbon in HCl. So HCl is an acid, infact a very strong acid; but not an organic acid.

on is a PROCESS in which a gas moves from a region of high concentration to a region of lower concentration.rate of diffusion is inversely proportional to the square root of MASS.now, in a CONTAINER, gas occupies the volume of the container.so gas A and gas B have same volume when placed in the same container.now mass is directly proportional to the density of the gas.so, d1/D2 = (m1/m2)^1/2 = (p1v/p2v)^1/2 = (p1/p2)^1/2d1, d2 rate of diffusion of gases a and b respectively.similarly, m is the mass of the gas,p is the density of the gas,v is the volume of the gas.u can easily remember the expression as,when something is heavier (or denser), it's more difficult for it to travel than something that's lighter than it.

s are formed because of big BANG of our UNIVERSE,our sun, dying of our STARS,HUMAN made elements

lastic1)Can be melted2)Can be moulded to any desired SHAPE any number of TIMES .3)It can be recycled4)It can be remelted  desired colour can be applied.Example: polythene,polystyreneThermosetting plastic1)Can not be melted2)Can be moulded to any desired shape only once3)It can not be recycled 4)After moulding it for the first time , remelting , changing colour is impossible .Example : melamine , bakelite

lute sulphuric ACID is POURED on a copper plate, bubbles appear on the surface of plate. becoz when metal is react with acid it's produce hydrogen gas.here copper is very reactive metal and very reactive acid is SULFURIC acid.reaction:H2SO4 + Cu -> CuSO4 + H2

in Tf (freezing temperature) = solvent's freezing point - SOLUTION's freezing point. (coz on addition of solute, freezing point tends to DECREASE)change in Tf = (0+273) - (-0.240+273) = 0.240 Kelvinchange in Tf = (i)(Kf)(m)i is van't hoff factorKf is freezing point depression constant.m is the molality.moles of solute= 0.5/(39 + 35.5)MASS of solvent in kg = 100/1000molality = moles of solute/ mass of solvent in kgKf is given.solve for i.next, (alpha) = (i-1)/(n-1)n is 2, since no. of moles formed after dissociation of kcl in water is 2 (k+ and cl-)alpha/100 is PERCENTAGE dissociation.

is OBTAINED from WOOD PULP.

is DEFINED as the AMOUNT of a substance that contains as MANY elementary entities as there are atoms present in exactly 0.012kg or 12 g of Carbon-12.

12x10^(-10)(n^2/Z) metren is ORBIT no. z is atomic number.here, n=2, z=2v=2.18X10^6(z/n) ms^(-1)E=31.6 (Z^2/ n^2) ev(ELECTRON volt)POTENTIAL energy= 2Ekinetic energy= -E

,GRAPHITE and WHITE CARBON are the allotropies of carbon.

universe ,whatever we MEASURE,to measure we need a standard.To learn the PROPERTY of gases we COMPARE the quality/ QUANTITY of gas with the  gas at S.T.P condition

: CH4  : molecular weight = 16So one MOLE of methane weighs 16 gm.At STP, one mole of  an ideal  GAS occupies 22.4 LITRES.  112 cm³ of methane contains :  112 / 22,400 = 0.005 MOLES.   mass of the gas = 0.005 * 16 gm = 0.080 gm = 80 milligrams

weight of metal M = 56in an oxide,  metal is  70% by mass        and so  oxygen is 30% by mass.let there be  n ATOMS of  oxygen PER 1 atom of metal.Then  proportion of the masses of metal and oxygen :               56 :  n * 16  = 70  : 30           16 n = 56 * 30 / 70                  n = 24/16 = 1.5There are two atoms of metal for 3 atoms of Oxygen.:        M2 O3

sage of an electric current through a solution CAUSES CHEMICAL  EFFECTS

for asking the question.Aluminum is used in thermite PROCESS as a reducing agent because it is inexpensive and EASILY available. Moreover it has a very high BOILING POINT. During the thermite process a LOT of heat is produced when aluminum is used which melts other metals too. So it is very advantageous.Hope it helps.

anced EQUATION is H2S+Cl2=S+2HCl

non planer and also trigonal planer shape and is symmetrical with all respects. And no contain free unpaired electron because florien is very electro negative   DIPOLE moment is 0.In NF3 PYRAMID type STRUCTURE and  florien is very electro negative so its RESULTANT dipole is downward and dipole is not 0

law states that : where p = partial pressure of the gas above the solution.    is the Henry's solubility constant for the solvent & solute at given T°C    c = molar CONCENTRATION  of the solute in the solution in  moles/Litre  at given T°Cp = 1 BAR    and    =71.18 kbar-Litre/mol   c = 1  / 71.18 * 10³ = 14.048 mol/Litre concentration =  14.048 mol/Litre  or    28.096 gms/Litre

number =Z= number of protons in an atomAs atom is electrically neutral, Number of protons =number of electrons.Once we know the number of electrons we can arrange the electrons in different shells and find out the valence electrons and valency.So valency of an atom is defined as its combining capacity which gives us an idea of how many electrons the atom will loose or gain to attain stability.hence its reactivity and chemical properties are also based on valency.Hence chemical property of an element is determined by its ATOMIC number.For example : OXYGEN - Atomic number =8electronic configuration-1s²2s²2p⁴It has 6 valence electrons and valency=2Hence its placed in Group  16 of periodic table with other ELEMENTS like sulphur ETC having the same chemical properties.

cThe geminal dihalides are boiled with AQUEOUS KOH or NaOH. It produces aldehydes and ketones. geminal dihalide (R-CHX2) having two halogen atoms situated on terminal carbon ATOM, are hydrolysed by aq. KOH or aq. NaOH FIRST produced a unstable dihydroxy compound. Then converts into an aldehyde by loss of water molecule. 1-1- dichloroethane is GERMINAL dihalide which REACT with KOH and produce unstable hydroxyl compound then loss of water molecule acetaldehyde produce See the attachment for reaction.

t cooler cools better on a hot dry DAY because on a hot dry day temperature is high and humidity is less which helps in better evaporation. Due to the HIGHER rate of evaporation it gives better COOLING effect.

ervation SHOWS the following PROPERTIES of matter: 1. The particles in a liquid can be displayed EASILY from the original positions.2. The INTERMOLECULAR attractive force in the liquid is not very strong.3. Liquid exhibit FLUIDITY they can flow easily.================================Hope this will help you.....

fibre;- all NATURAL fibre COMES from nature.SYNTHETIC fibres are completely  man made.natural fibre;-fibres are found in staple or filament form.other other HAND,synthetic fibres found in filament form but sometimes it could it could be converted  into staple or CUT length.

ry SIMPLE u should read the EQUATIONS  properly the reactants as well as the products formed.them form a reaction and balance them.and write each EQUATION 5 times by practising more and more u will gain CONFIDENCE

s insoluble in water because of water's dipole strength. SINCE barium SULPHATE has strong crystals , water's dipole strength is too weak to PULL away the ions  (ANIONS and cations)  from it

ays are positively charged PARTICLES PRODUCED in the discharge TUBE. Proton is the Canal ray PARTICLE which is deflected TOWARDS negative of electric field.

ne is a terminal alkyne and carbon in acetylene (or in general in a alkyne) is sp hybridised. As in sp HYBRIDISATION s CHARACTER is 50%(as compared to 25% in SP3 and 33.3% in sp2) and we know that the more is s character the more is the penetration power and hence more is the electroNegativity. Since in any TERMINAL ALKYNE LIKE ACETYLENE carbon is BONDED only to a hydrogen which is fairly less electronegtive than carbon so the sp character of carbon allows it to hog or take the electrons of one hydrogen quite easily and in this process itself becomes negatively charged and therefore h+ is released. This makes the acetylene acidic (acidic means to give h+) Sodium +acetylene = sodium acetalinide (na c triple bond c na)+ h2 (sodium reacts only with water and acids to give hydrogen and both are acidic which again shows that acetylene is acidic in nature) Acetylene +tollens reagent = silver mirror of Ag (s)[gives positive tollens TEST which shows its acidic character]

,000 litres      P1 = 800 mm Hg          T1 = -3 °C = 270°K     Volume of a cylinder = 10 litresLet there be n cylinders used to fill all the gas from the tank.     V2 = 10 * n  litres.      T2 = 0 °C = 273 °K      P2 = 400 mm HgThe ideal gas law states that :       P1  V1 / T1  =  P2 V2 / T2        V2 =  P1 V1 T2 / (T1 P2)             = 800 * 10,000 * 273 / (270 * 400)             = 20, 222.22  litres             = 10 * n      n = 2, 022.22 cylinders           or  2, 023 cylinders  with the LAST  cylinder having less of the gas as compared to the other cylinders.

easing pressure. example. water can be distiled out at 50℃ by increasing pressure.when you increas the pressure molecules of gas are come CLOSER and become chang the STATE. also by decreasing TEMPERATURE.