Chemistry · Science General

Common Chemical Compounds and Reactions

1,197 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.

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Common Chemical Compounds and Reactions Questions

Multiple choice chemistry p- block elements-ii compounds of phosphorus- pcl5 phosphorus halides compounds of phosphorus compounds of phosphorus - pcl3

Identify the correct statements.

  1. Calcium cyanamide on treatment with steam under pressure gives ${NH _3}$ and ${Ca CO _3}$
  2. ${PCl _5}$ is kept in well stopped bottle because it reacts readily with moisture

  3. Ammonium nitrite on heating gives ammonia and nitrous acid
  4. Cane sugar reacts with conc. ${H NO _3}$ to form oxalic acid
Reveal answer Fill a bubble to check yourself
A,B,D Correct answer
Explanation

(A) Calcium cyanamide on treatment with steam under pressure gives ${NH _3}$ and ${Ca CO _3}$
 $\displaystyle CaCN _2+3H _2O \text { (steam)} \xrightarrow {\displaystyle \text {3 atm}} CaCO _3+ 2NH _3$
(B) ${PCl _5}$ is kept in well stopped bottle because it reacts readily with moisture
 $\displaystyle PCl _5+H _2O \rightarrow POCl _3+2HCl$
 $\displaystyle PCl _5+4H _2O \rightarrow H _3PO _4+5HCl$
(C) Ammonium nitrite on heating gives nitrogen and water.
 $\displaystyle NH _4NO _2 \rightarrow N _2  +2H _2O$
(D)Cane sugar reacts with conc. ${H NO _3}$ to form oxalic acid
 $\displaystyle C _{12}H _{22}O _{11}+36HNO _3 \rightarrow 6(COOH) _2+36NO _2+23H _2O$

Multiple choice chemistry p- block elements-ii compounds of phosphorus- pcl5 phosphorus halides compounds of phosphorus compounds of phosphorus - pcl3

The solid $PCl _5$ exists as :

  1. $PCl _3$
  2. $PCl _4^+$
  3. $PCl _6^-$
  4. $PCl _4^+$ and $PCl _6^-$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

In solid state, $PCl _5$  prefers to exist as oppositely charged ions like $[PCl _4]^+$ & $[PCl _6]^-$ as the ionic bonding enhances the crystalline nature.

Also, $[PCl _4]^+$ is tetrahedral while $[PCl _6]^-$ is octahedral, these structures fit well into each other providing extra stability to the soild structure.

Multiple choice chemistry p- block elements-ii compounds of phosphorus- pcl5 phosphorus halides compounds of phosphorus compounds of phosphorus - pcl3

Solid crystalline $PCI _5$ has structure which of the following?

  1. Bi-pyramidal

  2. Octahedral and tetrahedral ions

  3. Square-pyramidal

  4. Pentagonal

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

In solid state, $PCl _5$ prefers to exist as oppositely charged ions like $[PCl _4]^+$ & $[PCl _6]^-$ as the ionic bonding enhances the crystalline nature. Also, $[PCl _4]^+$ is tetrahedral while $[PCl _6]^-$ is octahedral, these structures fit well into each other providing extra stability to the soild structure.

Multiple choice botany micro - organism fungi: benefits and harmful effects useful and harmful fungi uses of fungi

Calcium gluconate is widely used as a source of calcium for infants. It is prepared from

  1. Rhizopus

  2. Aspergillus

  3. Mucor

  4. None of the above
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Aspergillus niger is filamentous fungi that cause disease on vegetables and fruits called black mould. These organisms are used in fermentation processes to obtain citric acid and gluconic acid that are of commercial importance. It is also used in the manufacture of calcium gluconate. This compound is given to infants from hypocalcemia. Thus, the correct answer is option B.

Multiple choice chemistry changes around us crystallisation process of separating components of a mixture physical changes

One of most common solvent used for crystallization is:

  1. syrup

  2. normal saline

  3. water

  4. sulphuric acid
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

One of the most common solvents is water. It is also called as a universal solvent.

Crystallization is the process of formation of crystals. Since water can be easily added or removed from the system. It is the most common for eg. ${ CuSO } _{ 4 }.5{ H } _{ 2 }O$
                                     ${ Fe } _{ 2 }{ O } _{ 3 }.n{ H } _{ 2 }O$

Multiple choice chemistry changes around us crystallisation process of separating components of a mixture physical changes

Which of the following represents correct statement(s)?

  1. Salt can be obtained by the evaporation of sea water.

  2. The salt obtained during crystallisation is pure and its crystals are large.

  3. After crystallisation, the shape of the crystals can be seen clearly.

  4. Large crystals of pure substances cannot be formed from their solutions.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The option (A) represents correct statements.
Salt can be obtained by the evaporation of sea water.
The salt obtained during crystallisation is not pure and its crystals are small.
After crystallisation, the shape of the crystals cannot be seen clearly.
Large crystals of pure substances can be formed from their solutions.

Multiple choice applications of adsorption adsorption adsorption and colloids surface chemistry chemistry

Which of the following is used to adsorb water?

  1. Silica gel

  2. Calcium acetate

  3. Hair gel

  4. Cheese
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Silica gel has a very strong affinity for water and will adsorb it in preference to most other substances. It is also a good adsorbent for HCl, gasoline-range hydrocarbons, sulphur and nitrogen compounds, aromatics and many others. Silica Gel is in wide use in many industries for a myriad number of applications where a high capacity desiccant or selective adsorbent is required.

Multiple choice applications of adsorption adsorption adsorption and colloids surface chemistry chemistry

Which of the following is/are true statement(s)?

  1. Water vapour is absorbed by anhydrous calcium chloride while it is adsorbed by silica gel.
  2. $NH _3$ is absorbed by water but adsorbed by charcoal.

  3. Sugar is decolourized by animal charcoal based on adsorption.
  4. Water is absorbed by conc. $H _2SO _4$.
Reveal answer Fill a bubble to check yourself
A,B,C,D Correct answer
Explanation

Adsorption is the adhesion of atoms, ions, or molecules from a gas, liquid, or dissolved solid to a surface. This process creates a film of the adsorbate on the surface of the adsorbent.
Absorption is a physical or chemical phenomenon or a process in which atoms, molecules or ions enter some bulk phase – gas, liquid or solid material.

a) Water vapour is absorbed by anhydrous calcium chloride while it is adsorbed by silica gel.
b) Ammonia is absorbed by water but adsorbed by charcoal.
c) Decolourisation of sugar solution by activated charcoal is another example of adsorption. Charcoal absorbs the colouring material and thus decolourising the solution.
d) Water is absorbed by sulphuric acid because both are in same phase.
NHis absorbed by water but adsorbed by charcoal.

Multiple choice basics of management of water environmental science conservation of resources food production: soil and water management biology

.......... is used in seeding clouds.

  1. Potassium iodide

  2. Calcium carbonate

  3. Sulphur dioxide

  4. Ammonium phosphate
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
  • An artificial method of rain is called seeding cloud. It is a type of weather modification. 
  • This method aims at to change the amount of precipitation which falls from clouds. The method uses seeding of certain substances into the air that will serve as cloud condensation. 
  • In this, tiny particles like potassium iodide or dry ice are seeded (sprayed) in the atmosphere. 
  • The water present in the air is attracted and condenses near the sprayed particles. 
  • It further crystallises to form ice. Finally, it causes the rainfall. 
  • Thus, the correct answer is option A.
Multiple choice evs water: a precious resource importance of water let's play with water water and its properties water resources and conservation

A sample of water contains sodium chloride and magnesium chloride. Which of the following is not applicable to this?

  1. It is hard water because magnesium chloride is dissolved in it.

  2. It is hard water because sodium chloride is dissolved in it.

  3. A is hard water because it given only small amount of froth.
  4. It is a hard water because it leaves solid residue on evaporation which given test for $Mg^{2+}$.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Hard water contains chlorides, carbonates and bicarbonates of sodium and magnesium ions which combine with soap micelles and do not give lather with soap.

Multiple choice chemistry study of compounds a. hydrogen chloride laboratory method of preparation of hydrochloric acid physical and chemical properties and uses of hydrochloric acid hydrogen chloride: occurrence, preparation, purification and identification

Drying agents used in the purification of hydrogen chloride is/are:

  1. conc. $H _2SO _4$
  2. $P _2O _5$
  3. $CaO$

  4. all of the above
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Conc. $H _2SO _4$ is a very strong drying agent and it is used in purification of hydrogen chloride.

Multiple choice chemistry study of compounds a. hydrogen chloride laboratory method of preparation of hydrochloric acid physical and chemical properties and uses of hydrochloric acid hydrogen chloride: occurrence, preparation, purification and identification

Glaber prepared $HCl$ from which of the following compounds?

  1. $NaCl,H _2SO _4$
  2. $NaCl,H _2CO _3$
  3. $NaCl,HNO _3$
  4. $KCl,H _2SO _4$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Glaber is the scientist who prepared hydrogen chloride in the laboratory by reacting sodium chloride with concentrated sulphuric acid.

$NaCl+H _2SO _4\rightarrow NaHSO _4+HCl$

Sodium bisulphate is a by-product in the above reaction . This is insoluble. Therefore, we further add it with more sodium chloride. This mixture has to be heated to a higher temperature of around 823K. It gives dissolvable sodium sulfate and HCl gas.

$NaHSO _4+NaCl\rightarrow Na _2SO _4+HCl$.

Hence option $A$ is correct.