Which halogen is the most reactive?
a) Fluorine
b) Chlorine
c) Bromine
d) Iodine
Answer: a
NaHCO₃ is the chemical formula of:
a) Borax
b) Vinegar
c) Lime
d) Baking soda
Answer: d
Which gas is used in the production of vegetable ghee?
a) Hydrogen
b) Helium
c) Oxygen
d) Nitrogen
Answer: a
Which non-metal exists as a liquid at room temperature?
a) Bromine
b) Nitrogen
c) Fluorine
d) Chlorine
Answer: a
What is the molecular formula of ozone?
a) O₃
b) H₂O₂
c) Cl₂O
d) N₂O
Answer: a
Which chemical is commonly used to dehydrate water?
a) Bleaching powder
b) Alum
c) Borax
d) Soda powder
Answer: a
Why is barium used before stomach X-rays?
a) It’s transparent to X-rays
b) It enhances X-ray contrast by absorbing X-rays
c) It appears clearly in contrast with other regions
d) It’s white in color
Answer: c
Why does lime water turn milky when exposed to air?
a) Due to carbon dioxide
b) Due to nitrogen
c) Due to oxygen
d) Due to sulfur dioxide
Answer: a
Which of the following is used as a lubricant?
a) Graphite
b) Silica
c) Iron oxide
d) Diamond
Answer: a
Chemically, lime water is:
a) Calcium hydroxide
b) Sodium carbonate
c) Sodium hydroxide
d) Calcium carbonate
Answer: a
Assertion: Sodium is stored under kerosene. Reason: It reacts with air.
a) Both A and R are true, and R explains A
b) Both A and R are true, but R doesn’t explain A
c) A is true, but R is false
d) A is false, but R is true
Answer: c
Mercury is:
a) A solid metal
b) A liquid metal
c) A solid non-metal
d) A liquid non-metal
Answer: b
Electrodes in rechargeable torchlight batteries are made of:
a) Nickel and cadmium
b) Zinc and carbon
c) Lead peroxide and lead
d) Iron and cadmium
Answer: a
Diamond does not conduct electricity because:
a) It has a compact structure
b) It’s crystalline
c) It has only carbon atoms
d) It lacks free electrons
Answer: d
Aqueous copper sulphate is acidic because it undergoes:
a) Dialysis
b) Electrolysis
c) Hydrolysis
d) Photolysis
Answer: c
Charcoal acts in water treatment as a:
a) Solvent
b) Absorbent
c) Coagulant
d) Adsorbent
Answer: d
What is the chemical formula of heavy water?
a) H₂O
b) HDO
c) D₂O
d) H₂O₂
Answer: c
What is formed when hydrogen peroxide loses active oxygen?
a) Water
b) Hydrogen
c) Ozone
d) Nascent hydrogen
Answer: a
Which gas dissolved in water makes it basic?
a) Hydrogen
b) Carbon dioxide
c) Sulfur dioxide
d) Ammonia
Answer: d
Silicon is a polymer of:
a) Silicon tetrachloride
b) Dialkyl dichlorosilane
c) Silane
d) Tetraalkylsilane
Answer: b
Match the following compounds with their chemical names:
A. Bleaching powder – 1. Calcium oxychloride
B. Gypsum – 2. Calcium sulphate
C. Marble – 3. Calcium carbonate
Code: A–1, B–2, C–3
Answer: a
Which oxide is amphoteric in nature?
a) CaO
b) CO₂
c) SiO₂
d) SnO₂
Answer: d
Which of the following is NOT a form of carbon?
a) Graphite
b) Charcoal
c) Soot
d) Hematite
Answer: d
Material used in making lead pencils is:
a) Graphite
b) Lead
c) Carbon
d) Mica
Answer: a
Which halogen is the most reactive?
a) Fluorine
b) Bromine
c) Iodine
d) Chlorine
Answer: a
Why do stainless steel cooking pans have copper bottoms?
a) Copper is cheaper
b) Copper conducts heat better than steel
c) Copper increases durability
d) Copper reflects heat well
Answer: b
Which non-metal exists as a liquid at room temperature?
a) Bromine
b) Nitrogen
c) Fluorine
d) Chlorine
Answer: a
What is the chemical formula of common salt?
a) H₂O
b) NaCl
c) KCl
d) HCl
Answer: b
The chemical name of ‘Hypo’ used in photography is:
a) Sodium thiosulphate
b) Sodium nitrate
c) Sodium chloride
d) Silver nitrate
Answer: a
Soda ash is the common name for:
a) Sodium hydroxide
b) Anhydrous sodium carbonate
c) Sodium bicarbonate
d) Hydrated sodium carbonate
Answer: d
‘Philosopher’s Wool’ is chemically known as:
a) Zinc oxide
b) Calcium oxide
c) Aluminium oxide
d) Magnesium oxide
Answer: a