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