1Chemistry

ChemistryATOMIC STRUCTURE

The structure of atom was dis-covered by

Niels Bohr The smallest unit of matter that

have all the characteristics of anelement

Atoms

Nucleus was discovered by

Rutherford Neutron was discovered by

J Chadwick What is the maximum number

of electrons that can be accom-modated in an orbital?

2 Which atom has only one elec-

tron?

Hydrogen The path of the electron accord-

ing to Niels Bohrs theory was

Orbit (Shell) Electron is looked upon as a

cloud of negative charge accord-ing to

Wave - mechanics theory The region of space around the

nucleus where there is a highprobability of finding an elec-tron is called

Orbital Who put forward the principle

of uncertainty?

Werner Heisenberg What do you mean by Avag-

adros number?

Number of particles in onemole of any substance

The wave nature of electronwas suggested by whom?

Louis De Broglie The number of electrons in oxy-

gen atom is

8 Who discovered electrons?

J. J. Thomson What are the neutrons and

protons in an atom collectivelyknown as?

Nucleons The scientist who introduced

the model of the atom similarto the solar system?

Rutherford What are isotopes?

Atoms having same atomicnumber but different massnumber.

Father of Periodic Table

DMITRI IVANOVICHMENDELEEV

JOHN DALTONJohn Dalton was born in aweavers family in England. Hebegan his career as a teacher atthe age of twelve. After sevenyears he became principal. In1808 he stated his atomic theoryof matter. According to histheory all matter is made upof very tiny particles, whichcannot be further brokendown. He called this tiny par-ticles as atoms. All the atomsof the same element behave inthe same way.

2Chemistry

What are isobars?

Atoms having same massnumber but different atomicnumber

What are isotones?

Atoms having equal numberof neutrons.

PERIODICCLASSIFICATION

What is the basis for modernclassification of the elements?

Atomic number What was the basis for

Mendeleev classification of el-ements?

Atomic weight The horizontal rows of ele-

ments in the periodic table arecalled

Periods Modern periodic table was de-

veloped by

Henry Moseley The vertical columns of the pe-

riodic table are called

Groups Which group contains the ele-

ments with largest atomic size?

First group As the size of the atom increases

the electronegativity

Decreases

What kind of elements gener-ally form coloured compounds?

Transition metals Who studied the relationship

between atomic volume andatomic weight?

Lothar Meyer The first group elements are

called

Alkali metals

How many groups are there inthe modern periodic table?

Eighteen A solution which turns red lit-

mus to blue is called

Alkaline The elements which show the

properties of both metals andnon metals are called

Metalloids Which period having the mini-

mum number of elements

First period The elements of the s-block and p-

block are together referred to as

Representative elements Where are the smallest atoms

seen at the modern periodictable?

Right hand top The different blocks of the Long

form periodic table are

s, p, d and f Where are the Largest atoms

seen at the periodic table?

Bottom left

Which period have the largestnumber of elements in the pe-riodic table?

The sixth period Which is the smallest atom?

Hydrogen The relative tendency of the at-

oms to attract electrons inchemical reactions is called

Electronegativity The scientist who prepared the

electronegativity scale

Linus Pauling

ELEMENTS Which is the first artificial ele-

ment?

Technetium Most electropositive elements

Francium or Caesium The element which shows high-

est electron affinity

Chlorine (348) The most common element in

the atmosphere

Nitrogen The natural element having

highest atomic weight

Uranium The heaviest gaseous element

Radon Most stable element

Lead The element which is used to coat

the photo copying drum of xerox

Selenium The element present in Thyroid

hormone

Iodine The element present in DNA

and RNA

Phosphorus

The outermost orbit of anatom is called

Valence shell.

The electrons present in theoutmost shell of an atom is

called

Valence electrons

SYMBOLS OF SOMECOMMON ELEMENTS

Sodium - Natrium - NaCopper - Cuprum - CuIron - Ferrum - FePotassium- Kalium - KSilver - Argentum - AgGold - Aurum - AuTin - Stannum - SnLed - Plumbum - Pb

3Chemistry

The element contained in seaweeds

Iodine The element which is the en-

emy of copper

Sulphur Most abundant element present

in our body

Oxygen Which element on adding to

natural rubber makes it lesssticky in hot weather and lesshard in cold weather?

Sulphur Which element can easily form

chains?

Carbon Which element in radioactive

form is used for determiningthe age of artifacts, relics, bonesetc of the past?

Carbon Which element has no neutrons

in it?

Hydrogen Which element is used as an

antiseptic?

Iodine Which element is used in medi-

cine, photography and makingdyes, gives off a violet vapourwhen heated?

Iodine Which is the most essential ele-

ment for plant growth?

Nitrogen Which element is highly

present in sea cucumber?

Vanadium Which element was named

inflammable air?

Hydrogen

METALS AND MINERALS Which is the best conductor of

electric current?

Silver The main ores of Aluminium

Bauxite and Cryolite Metals extracted from sea water

Magnesium and sodium Major metals present in Chlo-

roplast

Magnesium, Manganese,Copper and Iron

Most abundant metal present inblood

Potassium The hardest metal is

Chromium Noble metals

Silver, Platinum, Gold The first metal to be used by man

Copper King of metal is

Gold The metal of future

Titanium The metal found in the rocks of

moon /Lunar metal is

Titanium Metal used for the manufacture

of aeroplane

Titanium Metal present in the exhaust

gases of vehicles

Lead An important metal present in

the eyes of animals

Zinc Metal used in batteries of car

Lead Metal present in Insulin

Zinc

Electro positive elements:

An atom that loses one ormore electrons

Electro negative elements:

An atom that gains one ormore electrons

The element having the high-est boiling point

Rhenium The element having the largest

number of isotopes

Tin (10 isotopes) Element having highest reactivity

Fluorine Element used as bleaching

agent

Chlorine Most abundant element in the

earth crust

Oxygen The most abundant metal in the

earths crust ?

Aluminium Element having the highest

electronegativity

Fluorine The most abundant element in

the universe

Hydrogen The lightest element known is

Hydrogen The lightest metal is

Lithium Name the element kept by cov-

ering with paraffin

Lithium Element used in the manufac-

ture of insecticides

Chlorine

4Chemistry

Metal used in torch cell

Zinc What is the purest form of iron?

Wrought Iron Which mineral has the nick-

name fools gold?

Iron pyrites The earthy impurities present

in the ore are called

Gangue Which metal remains in liquid

state at 0C?

Mercury Ruby is mainly the oxide of

Aluminium The metal having highest boil-

ing point

Tungston The fusible substance obtained

when flux combines with thegangue is known as

Slag Write the name of three soft

metals:

Lithium, Sodium, Potassium Name three metals which are

in the liquid state on a hot day

Mercury, Gallium, Cesium Write the names of three met-

als which do not react withoxygen:

Silver, Platinum, Gold Bismuth Aurite is the mineral of

Gold Which chemical causes

Minamata disease?

Mercury Which alkali metal is denser

than water?

Lithium

The elements which undergochemical change losing elec-trons are in generally called

Metals What is the blue mineral of alu-

minium?

Lapislazuli Which is the black impure alu-

minium oxide mineral found innature?

Emery Which metal is essential for the

production of haemoglobin?

Iron What is a metallic radical

present in toilet soap?

Potassium Which metal is added to gold

for making ornaments?

Copper Which metal is contained in

chlorophyll?

Magnesium Which are the two metals kept

in kerosene?

Sodium, Potassium Which metal is used in the fila-

ments of electric lamps?

Tungsten Which metal has the highest

density?

Osmium

ALLOYS Bronze is an alloy of

Tin and copper Alloy having low melting point

Solder

Alloy used to make rock driller

Manganese Alloy used to make springs and

suspension

Phospher Bronze Constituent metals contained in

the alloy sterling silver

Copper and silver Alloy used in the manufacture

of gun barrels

Gun metal Constituent metals contained in

chrome steel

Iron and Chromium Alloy used in the manufacture

of pendulum of clock

Invar Constituent metals contained in

Invar

Iron and Nickel Which is the first alloy, a mix-

ture of two metals to be madein the world?

Bronze Which alloy is used for prepar-

ing strong magnets

Alnico Name the alloy used for cast-

ing engine parts?

Silumin Alloy used for the construction

of air craft

Duralumin

What is galvanising

Coating iron with Zinc What do you mean by calci-

nation?

Heating in the absenceof air

5Chemistry

Alloy used for making super-structures of steamers

Magnalium Which alloy of aluminium is

used for making coins?

Aluminium bronze What is alloyed with copper to

make bronze, and with lead tomake pewter?

Tin The components of Magnalium

are

Magnesium, Aluminium Which kind of steel is used for

making blade?

High carbon steel What are the components of

solder?

tin and lead The heating element of an elec-

tric heater is made of

Nichrome

COMPOUNDS Photographic films are coated

with

Silver Bromide Artificial rain is done by using

Silver iodide Compound which has the smell

of rotten fish

Phosphine Coral reefs are made of

Calcium carbonate Compound used in tear gas

Benzyl chloride Compound used as airpurifier

in submarines

Sodium peroxide

Which is considered to be ananomalous compound?

Water Which chemical compound

may be used as a fuel for driv-ing vehicles?

Ethanol What is common salt?

Sodium chloride

What is caustic soda?

Sodium hydroxide What is Quick lime?

Calcium oxide Which calcium compound is

used to remove ice from roadsin cold countries?

Calcium chloride Which metal salt gives lilac

colour to the flame?

Potassium Which compound of sodium is

used to separate soap from glyc-erine?

Sodium chloride What is the difference between

lime and limestone?

Lime is calcium oxide, Lime-stone is calcium carbonate

What is the difference betweenquick lime and slaked lime?

Quick lime is calcium oxideand slaked lime is calciumhydroxide

Soda lime is a mixture of

Calciumoxide and Sodiumhydroxide (Quicklime andcaustic soda)

What is the main constituent ofbones?

Calcium phosphate The scales formed inside the

boilers are chemically

Calcium carbonate What is obtained when gypsum

is heated to 125C?

Plaster of paris The suspension of calcium hy-

droxide in water is called

Milk of lime or slaked lime Name the calcium compound

which is used as filler in paperindustry

Gypsum Which calcium compound is

used to make toothpaste?

Calcium carbonate When sodium burns, what is the

colour of the flame?

Golden yellow Which sodium compound is

used in fire extinguisher?

Sodium bicarbonate Which is the smallest atom

among the halogens?

Fluorine The iodine compound used for

dressing of wounds?

Iodoform (CHl3) What is the commercial name

of sodium nitrate?

Chile salt petre Name a substance which is used

as mordant

Alum

Chemical reaction in whichheat is evolved

Exothermic reaction

Chemical reaction in whichheat is absorbed

Endothermic reaction

6Chemistry

What is the chemical name ofEmerald?

Beryllium aluminium sillicate Which is the artificial form of

aluminium oxide used for mak-ing refractory crucibles?

Alundum Which form of aluminium

oxide is hard as diamond?

Corundum What is the colour of copper

sulphate?

Blue What is the chemical name of

verdigris?

Basic copper carbonate orbasic copper acetate

The copper compound used forpreserving timber and hides is

Copper sulphate Which chemical is used for rat

poison?

Zinc phosphide What is the chemical name for

marble?

Calcium carbonate Which salt is used in making

ink?

Ferrous sulphate Which chemical is used in a re-

frigerator for cooling purposes?

Freon What is the chemical name for

blue vitriol?

Copper sulphate What is the chemical name of

calamine?

Zinc carbonate Which chemical is used by

weavers for moisturing thread?

Anhydrous calcium chloride

What is the chemical name ofbaking soda?

Sodium bicarbonate What is an Epsom salt?

Magnesium sulphate What is the name for the green-

blue coating that forms natu-rally on copper, bronze andbrass?

Verdigris What is P.V.C.?

Poly Vinyl Chloride What is the chemical name for

saltpetre?

Potassium Nitrate Coffee stains on clothing, pa-

per, plastic etc can be properlyremoved by

Sodium hypochlorite Which substance is used for dry

cleaning?

Trichloro ethane What is the chemical name for

Galena?

Lead sulphite Which chemical is used for pre-

serving fruit juice in India?

Sodium Benzoate Most abundant alkali metal is

Sodium (Na) The whitest compound in the

earths atmosphere is

Titanium dioxide The compound known as Ni-

tre is

Potassium nitrate Which compound is known as

Pearl Ash

Potassium carbonate (K2CO2) The chemical name of washing

soda is

Sodium carbonate

ACIDS AND GASES The densest known gas

Radon The acid used as a mild antisep-

tic eye lotion?

Boric Acid What is hydroxy propionic acid

called

Lactic Acid Soda water contains which acid?

Carbonic Acid What is called vinegar?

3-7% solution of acetic acid Which gas is used for killing

bacteria?

Chlorine Proteins are assembled from

which acid?

Amino acid Oranges contains which acid?

Citric acid What is the another name for

monocarboxylic acid?

Fatty acid Where is formic acid found?

Ants and nettles

NOBLE GASES

Helium, Neon, Argon,Krypton, Xenon, and Radon

are Noble gases. They arecalled Inert Gases as theydo not enter into chemicalreactions and also called

Rare gases as they arepresent in very smallquantities in the air

7Chemistry

Which gas is filled in electricbulbs?

Argon Which gas is commonly used

in balloons and airships?

Helium Which acid is contained in

Tomato sauce?

Acetic acid Which gas protects us from the

ultra - violet rays?

Ozone Gas contained in Gobar gas

Methane The solution of ammonia gas

at high pressure is

Liquor ammonia Gold and platinum dissolve in

Aqua regia Which is the solvent for white

phosphorus?

Carbon disulphide Which polysaccharide of glu-

cose is stored in liver?

Glycogen What is laughing gas?

Nitrous oxide What is meant by aqua regia?

Mixture of concentrated ni-tric acid and hydrochloricacid in the ratio 1:3

Which is the solvent of wax?

Turpentine Which gas turns lime water

milky?

Carbondioxide Which is known as the king of

chemicals?

Sulphuric acid What is the other name of solid

carbon dioxide?

Dry Ice Which gas is used in the multi -

coloured display signs seen atnight?

Neon Which acid is commonly used

in batteries for cars?

Sulphuric acid Which acid is found in lemon fruit?

Citric Acid Which gas is used for extin-

guishing fire?

Carbondioxide What is the name of the dye

which turns red on contact withacid and blue with alkali?

Litmus What do you mean by LSD?

Lysergic acid diethylamide What is the pH factor of pure

water?

7 Gas formed when yeast is added

to rice flour for fermenting is

Carbon dioxide Which is the purest form of wa-

ter?

Rain water Some unripe fruits, like green

apples, plums etc contain whichacid?

Maleic acid What is the chemical name of

aspirin?

Acetyl salicylic acid

What is oil of vitriol?

Sulphuric acid What is an Acid - base indicator?

Methyl orange Stains of ink or rust from iron

on clothes, tables and sheets canbe best removed by

Oxalic acid Which gas is essential for com-

bustion?

Oxygen Irritation from the bite of some

insects and the stinging sensa-tion of nettles is caused by

Formic acid Gas mainly responsible for the

green house effect

CO2 Which is the main constituent

of LPG?

Butane Which gas is used for artificial

ripening of green fruits?

Acetylene (ethyne)

ORGANIC CHEMISTRY An organic compound must

contain

Carbon Marsh gas is

Methane Which compound is formed

when sugar solution is fer-mented?

Ethanol

CORROSIONThe process of damage ofmetals by the action of anymedium from its surround-ings is called Corrosion ofmetals

Bases are substancewhich neutralise acids.Eg : CaO, MgO, CuO etc.

Soluble bases arecalled alkaliesEg : NaOH, KOH

8Chemistry

Name the solution used to de-tect the presence of glucose:

Benedict solution Give an example of polysaccha-

ride

Cellulose The simplest member of satu-

rated hydrocarbon is

Methane (CH4) Which is the first organic com-

pound artificially prepared?

Urea Name a simplest amino acid

Glycine Which is the chemical bond

found in organic compounds?

Covalent bond Which is the enzyme that con-

verts the starch in our food intoglucose?

Amylase Who discovered the pesticide

property of DDT?

Paul Herman Muler Vinegar is chemically

Acetic acid (CH3COOH) Hydrocarbon with double

bond is

Alkenes What is the commercial name

of acetylene tetrachloride?

Westrol The organic compounds having

the functional group COOH arecalled

Carboxylic acids Carbohydrate which human

beings cannot digest

Cellulose Which organic compound have

the functional group OH?

Alcohol

Compound having the samemolecular formula but differ-ent structural formula arecalled?

Isomers What is another name of al-

kanes?

Paraffins What is obtained when an acid

reacts with an alcohol?

Ester What is another name of Me-

thyl alcohol or methanol?

Wood spirit What is another name of Alk-

enes?

Olefins Unsaturated hydrocarbons with

triple bond

Alkynes What is the end product of hy-

drolysis of protein?

Amino acids

What is the name of the gasused in the preparation ofpolythene?

Ethylene Write a carbohydrate insoluble

in water:

Starch Which is the hardest form of

carbon, whose crystals are oc-tahedral in shape?

Diamond Milk protein is known as

Caesin The sugar contained in honey

is

Fructose The hard, plastic covers of tele-

phones are made of polymers

Phenol - formaldehyde Lead pencils are made of

Graphite - an allotrope ofcarbon

FUELS The substances which burn and

supply energy are called

Fuels Which is the main constituent

of natural gas?

Methane Which substance is obtained

when coal is heated in the ab-sence of air?

Coke Coal containing a large amount

of carbon is

Anthracite What is the colour of crude pe-

troleum?

Brown

pH VALUESThe measure of the

acidic or basic characterof a liquid or solution is

the pH value.

The pH scale wasintroduced by

Sorrenson.

pH value generallystarts from 0 and ends at

14.

Neutral solution havepH 7.

Acidic solution have pHless than 7 and basic

solution have pHgreater than 7

9Chemistry

What is meant by ignition tem-perature?

The temperature at which afuel starts burning whenheated is called ignitiontemperature.

How can petroleum be puri-fied?

Fractional distillation Which is the main constituent

of petroleum gas?

Butane What is formed by the mixture

of hydrogen, methane and car-bon monoxide?

Coal gas Which fuel is used in aeroplane?

Aviation spirit What are the components of

natural gas?

Methane and hydrogen Coal containing 65% of carbon

Bituminous coal

MAN MADE MATERIALS Cement mixed with gravel,

sand and water is called

Concrete Which product of living organ-

isms was the first to be madeunder laboratory conditions?

Urea

Which drug is present in tobacco?

Nicotine Optical glass is

Flint glass Which glass is generally used

for making laboratory wires?

Heat resistant glass Substance used to give violet

colour to glass

Manganese dioxide Which glass is used for making

lens?

Flint glass Cobalt compounds give which

colour to glass?

Blue Raw material commonly used

for all types of glass

Silica Which glass is used as the wind

shield of the motor cars?

Safety glass (laminated glass) Which glass is used for making

electric bulb?

Soda glass Ferrous oxide gives which

colour to glass?

Olive green Which substance is added for

getting yellow colour to glass?

Chromium salt

What is used for makingprisms?

Flint glass Which laminates are used for

making helmets?

Fibre glass Which substance is used for

making PVC?

Vinyl chloride Which plastic acquires hardness

permanently when heated andcooled?

Thermosetting plastics Which type of plastics is used for

making adhesives, button etc?

Urea formaldehyde What is widely used for mak-

ing nylon?

Caprolactum What is used for salting out, in

the manufacture of soap?

Sodium chloride Which solvent is used for dry-

cleaning of clothes?

tetrachloro ethylene Which sweet-smelling solvent

is used in Nailpolishes?

Acetone What is the chemical content of

moth balls?

Naphthalene Which artificial fibre is used for

making fishing net?

Nylon What is the chemical name for

factomphos?

Ammonium carbonate Write the process which causes

bread to rise and producebubbles in beer:

Fermentation

Common Name .......................................... Chemical NameCarborundum.................................................. Silicon carbideNitre ............................................................ Potassium nitrateHypo ..................................................... Sodium thiosulphateSpirit .................................................................. Ethyl alcoholLunar caustics .................................................... Silver nitrateGreen Vitriol ...................................................... Iron sulphateQuartz ............................................................ Silicon dioxide

10

Chemistry

Which chemical fertilizer isfound in chile?

Sodium nitrate Antibiotic used in the treatment

of typhoid fever

Chloramphenicol What do you call the substances

which bring down the bodytemperature due to fever?

Antipyretics Scientist who first prepared

urea

Wohler What is the monomer of

polythene?

Ethylene What is the other name for

terylene?

Decorn Which fiber is chemcially iden-

tical to cotton fibres?

Rayon Detergents used for cleaning

clothes and utensils contain

Sulphates Which is used as a thickener in

paints and lipsticks?

Bentonite

Commonly used narcoticanalgesies are

Morphine, Codeine,Marijuane etc.

BIO-CHEMISTRY The branch of science which

deals with the treatment of dis-eases using suitable chemicalsis known as

chemotherapy What is the another name of

Ascorbic acid?

Vitamin C Which nucleic acid is mainly

responsible for the synthe-sis of protein?

Ribo nucleic Acid (RNA) Which nuclei acid is responsible

for heredity?

Deoxyribo Nucleic Acid(DNA)

What is the chemical name ofvitamin B1?

Thiamine What is riboflavin?

Vitamin B2 What is a sunshine vitamin?

Vitamin D Which enzyme can hydrolyse

sucrose?

Invertase What is cyanocobalamin?

Vitamin B12 Which is a steroid vitamin?

Vitamin D

What is ascorbic acid?

Vitamin C What is calciferol?

Vitamin D Which vitamin prevents pellagra?

Niacin The vitamin present in rice pol-

ishing is

Vitamin B2

RADIO ACTIVITY What are the three isotopes of

hydrogen?

Protium H1, Deuterium H2

and Tritium H3)

The process by which smallernuclear joins and forms largernucelus is called

Fusion reaction A heavy nucleus breaking up

into smaller nuclei of almostequal size is called

Fission Artificial Radio Activity was

discovered by

Irene Curie and F. Juliot Simplest Radioactive atom is

Tritium Age of fossils is calculated by

Radiocarbon dating Element used in Radiocarbon-

dating

Carbon 14 Wine dating is done by

Tritium

Natural Radioactivitywas discovered byHenry Bequerrel

Analgesics - Chemicals used for getting relief from painAntipyretics - Chemicals which bring down body temperatureAntiseptics - Chemicals which prevent the growth of micro

organisms and may even kill them.

11

Chemistry

Isotope used for cancer treat-ment

Cobalt 60 Angiogram test is done by us-

ing

Sodium 24 Isotope used for the treatment

of Leukaemia

Gold 198 Bone cancer can be diagnosed

by using

Phosphorus 32 Coolants used in nucelar reactor

Liquid sodium Moderators used in Nuclear

Reactor

Graphite and Heavy water Strongest Radioactive element

Radium Liquid Radioactive metal

Francium Gaseous Radioactive element

Radon Unit of Radioactivity

Bequerrel The principle of atom bomb

Uncontrolled chain reactionof nuclear fission

Radiocarbon dating was devel-oped by

Willard F. Libby Radioactivity is measured by

using the instrument

Geiger counter Isotope used for the treatment

of Hyperthyroidism

Iodine 131 The Radioactive element

present in Pitch Blende

Uranium Half life period of Carbon 14

5730 years Half life period of thorium 234

24 days Rays which travels in the speed

of light

Gamma rays

CHEMICAL EQUILIBRIUM The steady state from which no

spontaneous change takes placeis called

Equilibrium The chemical reactions which

never go to completion arecalled

Reversible reactions The reaction in which the for-

ward and backward reactionsoccur simultaneously is called

Reversible reaction Those reactions in which the

products cannot react and giveback the original reactants arecalled

Irreversible reactions The temperature most suited

for conducting an industrialprocess involving a reversible

reactions, most convenientlyand profitably is called

Optimum temperature The reaction in which product

molecules react and give backthe original reactants is called

Backward reaction A system of reacting substances

from which neither the reac-tants nor the products are takenaway or added to is called

Closed system

MISCELLANEOUS At what temperature water has

the maximum density?

4C A rain coat is made of

Polychloroethene The absence of cobalt in minute

quantities in human bodycauses

Pernicious anaemia Which material is used in dis-

play devices, such as digitalwatches?

Liquid crystal

Le Chatellier

Who put forward a prin-ciple relating to the equilib-rium system?

ACID RAINAcid rain is caused due

to industrial pollution. Gasessuch as Sulphur dioxide, Ni-trogen oxides etc. producedby industries, power plantsand vehicles rise up in the at-mosphere and react with wa-ter vapour and oxygen in theatmosphere to give sulphuricacid and nitric acid. They dis-solve in water and comedown with rain (acid rain). Itcauses damage to vegetationand fertility of soil.

12

Chemistry

Which drug is present in coladrinks?

Caffeine What is the modern standard for

relative atomic mass?

Carbon isotope with massnumber 12

What happens when an electronmoves nearer to the nucleus ofthe atom?

Its energy decreases What is molarity?

Number of moles of solutein one litre of the solution.

What do you mean by a buffersolution?

Solution which can maintainconstant PH

Which halogen is highly metal-lic in character?

Astatine Which gas has the smell of rot-

ten eggs?

Hydrogen sulphide The phenomenon by which the

same element exists in the samephysical state in different formsis known as

Allotropy

Isotopes - Atoms of the sameelement havingsame atomic num-ber but differentmass number.

Isobars - Atoms of differentelements whichhave the same massnumber but differ-ent atomic number.

Isotones - Atoms of differentelements whichcontain the samenumber of neu-trons.

Substances used for removingexcess of chlorine from textilesafter their bleaching are in gen-eral called

Antichlor The substances which are capable

of absorbing combined water orelements of water from mol-ecules of compounds are called

Dehydrating agent The substances which are ca-

pable of removing watervapour from other substancesare called

Drying agents Smell of white phosphorus

Garlic What is the acid present in milk?

Lactic acid What is the colour of chlorine?

Greenish yellow What is the colour of ruby?

Red Which mineral is known as

fools gold?

Iron pyrites The iron obtained direct from

the blast furnace is called

Pig iron What is agate?

Naturally occuring silica Which is the germicidal com-

ponent in bleaching powder? Chlorine

Write the name of a liquid inwhich phosphorous dissolves: Carbondisulphide

Which element is used as a dis-infectant, as a bleaching agentand to purify water? Chlorine

What is the common name forsodium chloride?

Salt

An enzyme which helps in di-gestion is

Protease What do you understand by 22

carat gold?

22 parts gold, 2 parts copper What is sublimation?

Converting a solid directlyinto its vapour

The ashes of plants contain al-kali metals, 90% of which is

Potassium Which gas turns litmus

colourless?

Chlorine What is the common name for

hydrogen hydroxide?

Water Who is known as the Father of

Polymer Science?

The German scientistHerman Staudinger

The substances which conductelectricity with the help of theions present in them are called

Electrolytes The atoms or groups of atoms that

carry electrical charge are called

Ions Which chemical reaction takes

place in a torch cell?

Chemical energy is con-verted into electrical energy.

The negative electrode is called

Cathode Substances, that do not conduct

electricity are called

Insulators Electrode that is connected to

the positive pole of the batteryis called

Anode

13

Chemistry

In a torch cell, which energy isconverted into electric energy?

Chemical What is isomerism?

Same molecular formulabut different structural for-mula

What material is used for cut-ting glass?

Diamond Sulphur is required in plants

as a nutrient element for

Making vitamins Proteins are mainly made up

of

Carbon, Hydrogen, Oxygenand Nitrogen

Amino acids are the buildingblocks of

Proteins Natural rubber is a polymer of

Isoprene Car tyre cords are made up of

nylon - 66 The drugs used to treat allergy

are called

Antihistamins Substances which prevent the

formation of acids in the stom-ach are called

Antacids 6 to 10% solution of acetic acid

Father ofModern Chemistry

Robert Boyle

is used as a preservative forvarious food items. It is com-monly known as

Vinegar Natural antioxidants are

Vitamin C and E The hardness of water is due to

the presence of which salts ?

Temporary hardness - Bicar-bonates of Calcium & Mag-nesiumPermananet hardness -Chlorides and sulphates ofCalcium & Magnesium

The most commonly used foodpreservative is

Sodium benzoate

Soaps are the salts ofweak acid and strongbase. Hence their solu-tion is alkaline.

Detergents are the saltsof strong acid andstrong base. Hencetheir solution will beneutral.

Aspirin is used as

an analgesic Paracetamol is used as

both analgesic and anti-pyretic

The drug used against AIDS is

AZT Which metal is used to make

CD

Aluminium The smallest particle of an ele-

ment or a compound, whichshows all the properties of thatsubstance is known as

molecule Non - stick kitchen wares are

coated with

Teflon LPG is a mixture of

Ethane, Propane and Butane The main component of LPG is

Butane The main component of natu-

ral gas is

Methane The proess of coating Iron with

Zinc is known as

Galvanisation

CHEMISTSElectron - J.J. ThomsonProton & Nucleus - Ernest RutherfordNeutron - James ChadwickHydrogen - Henry CavendishOxygen - PriestleyNitrogen - Daniel RutherfordSodium, Potassium,Aluminium - Humphry DavyCarbon di oxide - Joseph BlackpH scale - SorensenAtom - John DaltonAtom model - Niels Bohr

14

Chemistry

Which acid is known as theKing of Chemicals ?

Sulphuric acid The substances which prevent

ageing of food materials arecommonly known as

Anti oxidants A mixture of carbon monoxide

and nitrogen is called producer gas

A mixture of carbon monoxideand hydrogen is called

Water gas A solution of carbon dioxide gas

in water is called

Soda water Which gases are used for gas

welding ?

Oxygen and acetylene Rock cotton is

Asbestos When Iron rusts, its weight

increases Element extracted from

monozite sand is

Thorium The gas used in refrigerators

and ice plants

Ammonia (NH3) The mixture of uranium oxides

is commonly known as

Yellow cake Man made elements are com-

monly known as

Transuranics The inorganic elements or com-

pounds which occur naturallyin the earths crust are known as

minerals The mineral from which a

metal can be profitably ex-tracted are called

Ores The process of extraction of

metals from their ores, and thenrefining them for use is known as

metallurgy The main ore of aluminium is

Bauxite The main ore of iron is

Haematite

COMMON ALLOYSAlloy ConstituentsSteel Iron, CarbonStainless steel Iron, Nickel,

ChromiumBrass Copper & zincBronze Copper & tinDuralumin A l u m i n i u m ,

copper, Tracesof Magnesium &Manganese

Invar Iron and NickelAlnico A l u m i n i u m ,

Nickel, Cobalt &Iron

Solder Lead & Tin

SOME COMMON ACIDSSubstance AcidVinegar Acetic AcidOrange &Lemon Citric AcidCurd Lactic AcidTea Tannic AcidApple Maleic AcidTamarind Tartaric acid