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

Multiple choice evs experiments with water water and its types hard and soft water what floats - what sinks

Permanent hardness is due to presence of soluble salts of Mg and Ca in the form of chlorides and sulphates in ${H} _{2}O$. It can be removed by:

  1. boiling

  2. Clark's method
  3. treatment with ${Na} _{2}{CO} _{3}$

  4. all of these
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Answer:-

Sodium carbonate can remove temporary and permanent hardness from water. Sodium carbonate is soluble but calcium carbonate and magnesium carbonate are insoluble.
The carbonate ions from sodium carbonate react with the calcium and magnesium ions in the water to produce insoluble precipitates.

${{Ca}^{+2}} _{\left( aq. \right)} + {{Na} _{2}C{O} _{3}} _{\left( aq. \right)} \longrightarrow {CaC{O} _{3}} _{\left( s \right)}  + 2{{Na}^{+}} _{\left( aq. \right)}$
${{Mg}^{+2}} _{\left( aq. \right)} + {{Na} _{2}C{O} _{3}} _{\left( aq. \right)} \longrightarrow {MgC{O} _{3}} _{\left( s \right)}  + 2{{Na}^{+}} _{\left( aq. \right)}$

Multiple choice evs experiments with water water and its types hard and soft water what floats - what sinks

Permanent hardness is due to the presence of soluble salts of Mg and Ca in the form of chlorides and sulphates in ${ H } _{ 2 }O$. It can be removed by:

  1. boiling

  2. the Clark's method
  3. treatment with ${ Na } _{ 2 }{ CO } _{ 3 }$

  4. all of these.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Boiling and Clark's method are used for removing temporary hardness. They cannot be used for removing permanent hardness. Permanent hardness can be removed by treatment with $Na _2CO _3$ which takes place as follows:-

$Ca^{+2}(aq)+Na _2CO _3(aq)\longrightarrow CaCO _3(s)+2Na^{+}(aq)$
Due to the removal of dissolved $Ca^{+2}$ and $Mg^{+2}$ ions, there is no longer existence of salts which makes the water soft.

Multiple choice evs experiments with water water and its types hard and soft water what floats - what sinks

The formula for permutit or zeolite which is used as softer in ion-exchange method is:

  1. $NaAlSiO _{4}$
  2. $NaAlO _{2}$
  3. both $A$ and $B$
  4. $Na _{2}SO _{4}$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
Permutit is an artificial zeolite. It is sodium aluminium orthosilicate $Na _{2}Al _{2}Si _{2}O _{8}.xH _{2}O$.
$\underset {\text { permutit}}{Na _{2}Al _{2}Si _{2}O _{8}.xH _{2}O} + Ca^{2+}(or Mg^{2+}) \rightarrow  \underset {\text { exhausted permutit }}{Ca Al _{2}Si _{2}O _{8}.xH _{2}O} + 2Na^{+}$
Multiple choice chemistry nitrogen and sulfur ammonia-properties and uses ammonia compounds of nitrogen - ammonia

Ammonia cannot be dried over regular dehydrating agent like: 

  1. $H _{2}SO _{4}$
  2. $P _{2}O _{5}$
  3. Anhydrous $CaCl _{2}$

  4. None of these
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Ammonia cannot be dried by passing over conc. sulphuric acid because ammonia gas reacts chemically with conc. sulphuric acid to form ammonium sulphate.
2NH3 + H2SO4 (conc.) $\rightarrow$(NH4)2SO4.

Multiple choice chemistry nitrogen and sulfur ammonia-properties and uses ammonia compounds of nitrogen - ammonia

Ammonia is dried over:

  1. slaked lime
  2. conc. $H _2SO _4$

  3. quick lime
  4. $BaCl _2$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
-Ammonia is basic.Hence it can be dried by a basic agent .
So, $CaO$ can be used to dry $NH _3$.
-Slaked lime cannot be used to dry $NH _3$, But dry $Ca$$\left( OH \right) _{ 2 }$ can be used to dry $NH _3$.
-Concentrated $H _2SO _4$ react with $NH _3$ and cannot be used to dry it.
-$BaCl _2$ absorbs $NH _3$ and form $BaCl _2$$.$ $4NH _3$, hence it cannot be used to dry $NH _3$
Multiple choice chemistry nitrogen and sulfur ammonia-properties and uses ammonia compounds of nitrogen - ammonia

Which of the following chemicals has caused disasters by exploding in the holds of ships in harbours and in warehouses?

  1. Vinegar in bottles under pressure

  2. Ammonium nitrate

  3. Gold chloride

  4. Caustic soda
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Ammonium Nitrate caused an explosion at the Port of Texas City. A ship loaded with $NH _4NO _3$ docked at the Port erupted in flames.

Another ship also carrying $NH _4NO _3$ caught fire in the blast and exploded on the same day.

Multiple choice chemistry nitrogen and sulfur ammonia-properties and uses ammonia compounds of nitrogen - ammonia

When Ammonical common salt solution is saturated with carbon dioxide we obtain ?

  1. $NH _4HCO _3$
  2. $(NH _4) _2CO _3$
  3. $NaHCO _3$
  4. $Na _2CO _3$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Ammonical solution of common salt.

$CO _2+NH _3+NaCl+H _2O\longrightarrow NaHCO _3+NH _4Cl$
$\therefore$ By treating $CO _2$ with ammonical $NaCl$ we get sodium bicarbonate $(NaHCO _3)$ and ammonium sulphate.
Answer is option C.

Multiple choice biology digestion and absorption liver functions of the liver secretory organs

Which ones are bile salts

  1. Haemoglobin and biliverdin

  2. Bilirubin and biliverdin

  3. Bilirubin and haemoglobin

  4. Sodium glycolate and taurocholate
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Bile salts are primarily sodium and potassium salts of glycocholic and taurocholic acids. They are essential for the emulsification of fats.

Multiple choice

What is the chemical name for table salt?

  1. Sodium Chloride

  2. Sodium Iodine

  3. Sodium

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

Table salt is chemically known as sodium chloride, with the formula NaCl. It is an ionic compound.

Multiple choice

DMSO used as

  1. Chelating agent

  2. Solidifing agent

  3. Cryoprotectant

  4. Gelling agent
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Dimethyl sulfoxide (DMSO) is a widely used cryoprotectant in cryopreservation. It prevents the formation of ice crystals that can damage cell membranes and intracellular structures during freezing.

Multiple choice

Which trace elements are found on smooth surfaces using superglue (Cyanoacrylate) fuming?

  1. Amino acids

  2. Fatty acids

  3. Proetins

  4. All of the Above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Cyanoacrylate (superglue) fuming is used to develop latent fingerprints on non-porous, smooth surfaces by reacting with the moisture and organic residues left behind. These residues consist of a mixture of amino acids, fatty acids, and proteins, all of which are stabilized and made visible by the polymerization of the glue. Therefore, all of these trace elements are involved in the process.