Chemical formula of water
Answer / solution
Correct option: B
Two hydrogen, one oxygen.
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Chemical formula of common salt
Answer / solution
Correct option: C
Sodium chloride.
Chemical formula of quicklime
Answer / solution
Correct option: C
Calcium oxide.
Chemical formula of slaked lime
Answer / solution
Correct option: B
Calcium hydroxide.
Chemical formula of washing soda
Answer / solution
Correct option: A
Hydrated sodium carbonate.
Chemical formula of baking soda
Answer / solution
Correct option: A
Sodium hydrogencarbonate.
Chemical formula of bleaching powder
Answer / solution
Correct option: A
Calcium oxychloride.
pH of a neutral solution at 25 °C
Answer / solution
Correct option: A
Equal H+ and OH−.
Acid turns blue litmus
Answer / solution
Correct option: D
Acidic.
Base turns red litmus
Answer / solution
Correct option: D
Basic.
Atomic number of carbon
Answer / solution
Correct option: B
6 protons.
Atomic number of oxygen
Answer / solution
Correct option: B
8 protons.
Atomic number of sodium
Answer / solution
Correct option: C
Na.
Atomic number of chlorine
Answer / solution
Correct option: D
Cl.
Atomic number of iron
Answer / solution
Correct option: B
Fe.
Atomic number of gold
Answer / solution
Correct option: C
Au.
Most abundant gas in air
Answer / solution
Correct option: C
About 78%.
Gas essential for combustion
Answer / solution
Correct option: A
Supports burning.
Photosynthesis gas released
Answer / solution
Correct option: C
From water splitting.
Greenhouse gas from burning fuel
Answer / solution
Correct option: A
Carbon dioxide.
Acid in vinegar
Answer / solution
Correct option: D
CH₃COOH.
Acid in lemon
Answer / solution
Correct option: B
Organic acid.
Acid in the stomach
Answer / solution
Correct option: D
Hydrochloric acid.
Valency of oxygen
Answer / solution
Correct option: B
Needs 2 electrons.
Valency of hydrogen
Answer / solution
Correct option: B
One electron.
Valency of sodium
Answer / solution
Correct option: C
Loses 1 e⁻.
Avogadro number (approx.)
Answer / solution
Correct option: A
Particles per mole.
One mole of any gas at STP occupies
Answer / solution
Correct option: C
Molar volume.
Atomic mass unit is defined using
Answer / solution
Correct option: D
1/12 of C-12.
Isotopes have same
Answer / solution
Correct option: D
Different neutrons.
Isobars have same
Answer / solution
Correct option: C
Different Z.
Isotones have same
Answer / solution
Correct option: B
Different Z and A.
Electron was discovered by
Answer / solution
Correct option: D
Cathode rays.
Nucleus was discovered by
Answer / solution
Correct option: D
Gold-foil experiment.
Neutron was discovered by
Answer / solution
Correct option: D
1932.
Periodic table modern basis
Answer / solution
Correct option: B
Moseley.
Group 1 elements are
Answer / solution
Correct option: D
Li to Fr.
Group 17 elements are
Answer / solution
Correct option: A
F to At.
Group 18 elements are
Answer / solution
Correct option: C
He to Rn.
Most electronegative element
Answer / solution
Correct option: C
Pauling scale.
Lightest noble gas
Answer / solution
Correct option: C
He.
Hardest natural substance
Answer / solution
Correct option: B
Carbon allotrope.
Allotropes of carbon include
Answer / solution
Correct option: B
Same element, different structure.
Rusting needs
Answer / solution
Correct option: A
Oxidation of iron.
Galvanisation coats iron with
Answer / solution
Correct option: A
Sacrificial protection.
Ore of aluminium
Answer / solution
Correct option: D
Al₂O₃·2H₂O type.
Ore of iron (common)
Answer / solution
Correct option: D
Fe₂O₃ / Fe₃O₄.
Metal extracted by electrolysis of melt (example)
Answer / solution
Correct option: C
Highly reactive metals.
Alloy of copper and zinc
Answer / solution
Correct option: B
Cu+Zn.
Alloy of copper and tin
Answer / solution
Correct option: B
Cu+Sn.
Steel is mainly
Answer / solution
Correct option: D
Controlled carbon.
pH < 7 means
Answer / solution
Correct option: C
More H+.
pH > 7 means
Answer / solution
Correct option: A
More OH−.
Strong acid example
Answer / solution
Correct option: C
Fully ionised.
Weak acid example
Answer / solution
Correct option: B
Partly ionised.
Neutralisation gives
Answer / solution
Correct option: A
Acid + base.
Oxidation is
Answer / solution
Correct option: D
OIL RIG.
Reduction is
Answer / solution
Correct option: A
OIL RIG.
Catalyst
Answer / solution
Correct option: A
Lowers activation energy (typical).
Endothermic reaction
Answer / solution
Correct option: B
ΔH positive (common convention).
Exothermic reaction
Answer / solution
Correct option: C
ΔH negative.
Saturated hydrocarbon example
Answer / solution
Correct option: B
Single bonds only.
Unsaturated hydrocarbon has
Answer / solution
Correct option: C
Alkene / alkyne.
Functional group of alcohol
Answer / solution
Correct option: D
Hydroxyl.
Functional group of carboxylic acid
Answer / solution
Correct option: C
Carboxyl.
Methane formula
Answer / solution
Correct option: B
Simplest alkane.
Ethene formula
Answer / solution
Correct option: A
Alkene.
Ethyne formula
Answer / solution
Correct option: A
Alkyne.
Ethanol formula
Answer / solution
Correct option: D
Alcohol.
Glucose formula
Answer / solution
Correct option: A
Simple sugar.
Ozone formula
Answer / solution
Correct option: C
Allotrope of oxygen.
Ammonia formula
Answer / solution
Correct option: B
Haber process product.
Haber process makes
Answer / solution
Correct option: B
N₂ + H₂.
Contact process makes
Answer / solution
Correct option: B
SO₃ route.
Ostwald process makes
Answer / solution
Correct option: D
From ammonia.
Hard water contains
Answer / solution
Correct option: B
Does not lather easily.
Temporary hardness is due to
Answer / solution
Correct option: D
Removed by boiling.
Permanent hardness is due to
Answer / solution
Correct option: A
Needs washing soda etc.
Soaps are
Answer / solution
Correct option: B
Cleansing in soft water.
Detergents work better in
Answer / solution
Correct option: D
Do not form scum as easily.
Atomic radius down a group
Answer / solution
Correct option: D
More shells.
Ionisation energy across a period
Answer / solution
Correct option: A
Harder to remove e⁻.
Metallic character down a group
Answer / solution
Correct option: A
Easier to lose e⁻.
Number of periods in long form table
Answer / solution
Correct option: B
7 horizontal rows.
Number of groups in long form table
Answer / solution
Correct option: C
Modern table.
s-block groups
Answer / solution
Correct option: A
ns electrons.
Noble gases have
Answer / solution
Correct option: A
Low reactivity.
Ionic bond example
Answer / solution
Correct option: D
Metal + non-metal.
Covalent bond example
Answer / solution
Correct option: B
Sharing electrons.
Coordinate bond example
Answer / solution
Correct option: A
Lone pair donation.
Hydrogen bond is important in
Answer / solution
Correct option: C
Strong intermolecular.
Molar mass of H₂O
Answer / solution
Correct option: C
2+16.
Molar mass of CO₂
Answer / solution
Correct option: C
12+32.
Molar mass of NaOH
Answer / solution
Correct option: D
23+16+1.
Molar mass of H₂SO₄
Answer / solution
Correct option: C
2+32+64.
Molar mass of NH₃
Answer / solution
Correct option: A
14+3.
Molar mass of CH₄
Answer / solution
Correct option: C
12+4.
Molar mass of O₂
Answer / solution
Correct option: A
16×2.
Molar mass of N₂
Answer / solution
Correct option: D
14×2.
Molar mass of CaCO₃
Answer / solution
Correct option: C
40+12+48.
Molar mass of NaCl
Answer / solution
Correct option: A
23+35.5.
Brown ring test is for
Answer / solution
Correct option: C
FeSO₄ + H₂SO₄.
Lime water turns milky with
Answer / solution
Correct option: B
CaCO₃ ppt.
Gas that turns lime water milky and is acidic
Answer / solution
Correct option: C
Carbon dioxide.
H₂S smells like
Answer / solution
Correct option: D
Toxic gas.
Chlorine is used as
Answer / solution
Correct option: B
Water treatment.
Iodine deficiency causes
Answer / solution
Correct option: D
Thyroid.
Iron deficiency causes
Answer / solution
Correct option: D
Haemoglobin.
Fluoride in water (excess) causes
Answer / solution
Correct option: D
Teeth/bones.
CFCs damage
Answer / solution
Correct option: B
Stratosphere.
Acid rain involves
Answer / solution
Correct option: B
From SOx NOx.
CNG is mainly
Answer / solution
Correct option: A
Compressed natural gas.
LPG is mainly
Answer / solution
Correct option: B
Liquefied petroleum gas.
Producer gas is
Answer / solution
Correct option: A
From coal/air.
Water gas is
Answer / solution
Correct option: D
From steam on coke.
Calorific value is
Answer / solution
Correct option: D
kJ/kg or kJ/mol.
Ideal gas equation
Answer / solution
Correct option: D
n moles.
Boyle’s law
Answer / solution
Correct option: D
Gases.
Charles’s law
Answer / solution
Correct option: C
Absolute T.
Gay-Lussac (P-T)
Answer / solution
Correct option: B
Absolute T.
First ionisation energy of noble gases is
Answer / solution
Correct option: C
Stable configuration.
Transition metals are in
Answer / solution
Correct option: C
Variable oxidation states.
Lanthanoids are
Answer / solution
Correct option: D
Rare earths.
Actinoids are
Answer / solution
Correct option: D
Many radioactive.
Benzene formula
Answer / solution
Correct option: B
Aromatic.
Phenol has
Answer / solution
Correct option: A
C₆H₅OH.
Aniline has
Answer / solution
Correct option: A
C₆H₅NH₂.
IUPAC name of CH₃COOH
Answer / solution
Correct option: D
Acetic acid common.
Saponification is
Answer / solution
Correct option: D
Soap making.
Polymer of ethene
Answer / solution
Correct option: B
Addition polymer.
Teflon monomer
Answer / solution
Correct option: A
PTFE.
Nylon-6,6 is a
Answer / solution
Correct option: A
Condensation polymer.
Bakelite is a
Answer / solution
Correct option: A
Phenol–formaldehyde.
Rate of reaction increases with
Answer / solution
Correct option: A
More successful collisions.
Activation energy is
Answer / solution
Correct option: D
Ea.
Buffer solution
Answer / solution
Correct option: C
Weak acid + salt (typical).
Faraday’s first law of electrolysis
Answer / solution
Correct option: C
m = ZIt.
Anode is where
Answer / solution
Correct option: D
Loss of electrons.
Cathode is where
Answer / solution
Correct option: A
Gain of electrons.
Electrolyte is
Answer / solution
Correct option: B
Ions free to move.
Distilled water is a
Answer / solution
Correct option: C
Few ions.
Blue vitriol is
Answer / solution
Correct option: C
Copper sulphate.
Green vitriol is
Answer / solution
Correct option: C
Ferrous sulphate.
White vitriol is
Answer / solution
Correct option: D
Zinc sulphate.
Gypsum is
Answer / solution
Correct option: C
Used in plaster.
Plaster of Paris is
Answer / solution
Correct option: A
From gypsum.
Marble / limestone is mainly
Answer / solution
Correct option: C
Calcium carbonate.
Glass is mainly
Answer / solution
Correct option: A
Supercooled liquid (often taught).
% composition: CO₂ — the value asked is
Answer / solution
Correct option: D
12/44×100 ≈ 27%
Number of atoms in one molecule of H₂SO₄ is
Answer / solution
Correct option: A
H₂SO₄ has 7 atoms.
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