Chemistry · Science General
Common Chemical Compounds and Reactions
1,204 Questions
Common chemical compounds and reactions questions test your knowledge of everyday chemicals, their formulas, and their interactions. Topics include properties of acids and bases, hard water chemistry, and compounds like baking soda and plaster of paris. This section is essential for general science preparation.
Acids and basesPlaster of parisHard water chemistryCommon chemical formulasEveryday chemical reactions
Common Chemical Compounds and Reactions Questions
-
Both chalk powder and salt will be completely dissolved making the water milky.
-
Chalk powder will first float, then settle down at the bottom and the salt will be fully dissolved.
-
Both salt and chalk powder will be undissolved.
-
Chalk powder will completely dissolve and salt will remain undissolved on the surface.
-
NA
B
Correct answer
Explanation
The same is correct because chalk powder will first float, then settle down at the bottom and the salt will be fully dissolved.
-
cleaning agent
-
drug
-
soap
-
catalyst
A
Correct answer
Explanation
A detergent is a cleaning agent that works by reducing surface tension and emulsifying oils, allowing water to wash away dirt and grease. Unlike soap (which is a specific type of detergent made from fats), detergents are synthetic compounds that work effectively in hard water.
-
calcium carbonate
-
sodium carbonate
-
calcium bicarbonate
-
sodium bicarbonate
B
Correct answer
Explanation
Washing soda is the common name for sodium carbonate decahydrate (Na2CO3·10H2O). It's called "washing" soda because it's widely used as a water softener in laundry and cleaning products. Sodium carbonate alone (anhydrous) is soda ash.
-
By dissolving solid in water
-
By observing the size of particles
-
By sieving
-
By heating
A
Correct answer
Explanation
Chalk powder is insoluble in water while salt completely dissolves, so adding water to each substance will clearly differentiate them - the chalk powder will remain as a solid residue at the bottom while salt will disappear into the water. Particle size observation and sieving won't work reliably since both can have similar particle sizes, and heating would just evaporate water from salt but leave both as solids.
-
Salt
-
Sugar
-
Baking powder
-
Chalk powder
A
Correct answer
Explanation
Salt (NaCl) dissolves fastest in water because it's an ionic compound that readily dissociates into Na+ and Cl- ions when in contact with water. Sugar takes longer to dissolve, baking powder is a mixture that reacts before fully dissolving, and chalk powder is mostly insoluble in water. The ionic nature of salt makes it highly soluble with quick dissolution kinetics.
-
Only a and b
-
Only a and c
-
Only a and d
-
Only b and c
-
Only c and d
E
Correct answer
Explanation
This is the correct option. Nitric acid solution and potassium hydroxide solution are strong electrolytes. They both contain lots of ions in them.
-
Aurum
-
Natrium
-
Stannous
-
Plumbum
-
Kalium
B
Correct answer
Explanation
Natrium is the Latin name of sodium.
-
Potassium Chlorate
-
Phosphorous pentoxide
-
Potassium Chloride
-
All the above
A
Correct answer
Explanation
The head of a safety match contains an oxidizing agent, typically potassium chlorate (KClO3), which provides oxygen to sustain combustion when the match is struck. Phosphorus pentoxide (P2O5) is not used on match heads. Potassium chloride (KCl) is different from potassium chlorate.
-
Potassium Chlorate
-
Potassium Chloride
-
Antimony Trisulphide
-
Red phosphorus
D
Correct answer
Explanation
In a safety match, the striking surface contains red phosphorus. When the match is struck, friction converts red phosphorus to white phosphorus, which ignites and initiates the combustion of potassium chlorate and antimony trisulfide on the match head. Red phosphorus on the side surface ignites FIRST, then transfers heat to the match head.
-
(III) and (IV)
-
(II) and (III)
-
(I), (II). (III) and (IV)
-
(I) and (IV)
C
Correct answer
Explanation
Safety match heads contain antimony trisulfide (the fuel), potassium chlorate (the oxidizing agent), and powdered glass (abrasive). The striking surface contains red phosphorus. When the match is struck, friction generates heat, the red phosphorus converts to white phosphorus, which ignites the potassium chlorate, starting the combustion of antimony trisulfide.
-
Copper oxide
-
Calcium oxide
-
Sodium hydroxide
-
Lime stone
C
Correct answer
Explanation
Sodium hydroxide is an alkali.
-
For making gun powder
-
For making fire cracker
-
For the preparation of sulphuric acid
-
As an antiseptic
-
Sulphur
-
Oxygen
-
Chlorine
-
Phosphorus
D
Correct answer
Explanation
Phosphorus (specifically red or white phosphorus) is used in matchbox industries, particularly on the striking surface of safety matches. When the match head is rubbed against this surface, the friction generates enough heat to ignite the phosphorus, which then ignites the match head. Sulphur is sometimes present in the match head itself, but the key material on the striking surface is phosphorus.
-
Jeweller's borax: Na2B4O7.10H2O
-
Fool's gold: FeS2
-
Gymnastic’s chalk: MgCO3
-
Photographer’s hypo: Na2S2O3.5H2O
-
Baker's ammonia: (NH4)2CO3
A
Correct answer
Explanation
Jeweller's borax (Na2B4O7. 5H2O) is the borax, which contains five molecules of water of crystallisation.
-
Only 1
-
1 and 2
-
1 and 3
-
1 and 4
-
2, 3 and 4
B
Correct answer
Explanation
The Solvay process or ammonia-soda process is the major industrial process for the production of soda ash (Sodium carbonate).
The principal byproduct of the Solvay process is calcium chloride (CaCl2) in aqueous solution.