Tag: substances in common use

Questions Related to substances in common use

Chemical formula of baking soda is:

chemistry substances in common use preparation, properties and uses of baking soda chemical from common salt compounds of carbon

  1. $MgSO _4$

  2. $Na _2CO _3$

  3. $NaHCO _3 $

  4. $MgCO _3$

Show answer
Correct Option: C
Explanation:

Chemical formula of baking soda is $NaHCO _3$.

Which of the following give brisk effervescence with baking soda ?

chemistry substances in common use preparation, properties and uses of baking soda chemical from common salt compounds of carbon

  1. methanoic acid

  2. propanoic acid

  3. ethanoic acid

  4. all of these

Show answer
Correct Option: D
Explanation:

The carboxylic acids react with baking soda to form sodium acetate, carbon dioxide and water. The general reaction can be written as:
$RCOOH + NaHCO _{3} \rightarrow CH _{3}COONa + CO _{2} + H _{2}O$
Thus the effervescence results from the release of carbon dioxide gas.

$NaHCO _{3}$ can be used on its own to make cakes or bread. Baking powder is more commonly used, and contains $NaHCO _{3}$, $Ca(H _{2}PO _{4}) _{2}$ and starch. An improved combination baking powder contains about 40% starch, 30% $NaHCO _{3}$ 20% $NaAl(SO _{4}) _{2}$ and 10% $Ca(H _{2}PO _{4}) _{2}.$ 

Answer the following questions based on above study.

Rise in bread and cakes is due to______ when it decomposes between $50^{o}C$ and $100^{o}C$. 

chemistry substances in common use preparation, properties and uses of baking soda chemical from common salt compounds of carbon

  1. $CO _{2}$

  2. $H _{2}O$

  3. both (a) and (b)

  4. none of these

Show answer
Correct Option: A
Explanation:
This happens due to reaction: $NaHCO _3+ H^+ \rightarrow Na^+ + CO _2+ H _2O$ 

The carbon dioxide produced in these reactions causes the dough to rise (ferment or prove), and the alcohol produced mostly evaporates from the dough during the baking process.

$NaHCO _{3}$ can be used on its own to make cakes or bread. Baking powder is more commonly used, and contains $NaHCO _{3}$, $Ca(H _{2}PO _{4}) _{2}$ and starch. An improved combination baking powder contains about 40% starch, 30% $NaHCO _{3}$ 20% $NaAl(SO _{4}) _{2}$ and 10% $Ca(H _{2}PO _{4}) _{2}$

Answer the following questions based on above study.


In improved baking powder, $NaAl(SO _{4}) _{2}$ is used for :

chemistry substances in common use preparation, properties and uses of baking soda chemical from common salt compounds of carbon

  1. makes the decomposition of $NaHCO _{3}$ faster

  2. slows the decomposition of $NaHCO _{3}$

  3. acts as filler

  4. makes the bread rise.

Show answer
Correct Option: B
Explanation:

Acid in a baking powder can be either fast-acting or slow-acting. $NaAl(SO _4) _2$ is a weak acid, it react with sodiumbicarbonate to produce $CO _2$ gas.

$NaAl(SO _4) _2 + 3NaHCO _3 \rightarrow AlOH _3 + 2Na _2SO _4 + 3CO _2$

$NaHCO _{3}$ can be used on its own to make cakes or bread. Baking powder is more commonly used, and contains $NaHCO _{3}$, $Ca(H _{2}PO _{4}) _{2}$ and starch. An improved combination baking powder contains about 40% starch, 30% $NaHCO _{3}$ 20% $NaAl(SO _{4}) _{2}$ and 10% $Ca(H _{2}PO _{4}) _{2}.$ 

Answer the following questions based on above study.

$Ca(H _{2}PO _{4}) _{2}$ in baking powder:

chemistry substances in common use preparation, properties and uses of baking soda chemical from common salt compounds of carbon

  1. behaves as an acid in moist condition and decomposes $NaHCO _{3}$ to give $CO _{2}$

  2. behaves as a base in moist condition and gives $H _{3}PO _{4}$

  3. behaves as a binder

  4. behaves as a filler

Show answer
Correct Option: A
Explanation:

Reaction of process:
$14 NaHCO _3+ 5 Ca(H _2PO _4)2H _2O\rightarrow 14 CO _2+ Ca _5(PO _4)3OH + 7 Na _2HPO _4+ 18 H _2O$


So Ca(H2PO4)2 in baking powder behaves as an acid  in moist condition and decomposes $NaHCO _3$ to give $CO _2$

${NaHCO _3+?\rightarrow NaCl+CO _2+H _2O}$ :

chemistry substances in common use preparation, properties and uses of baking soda chemical from common salt compounds of carbon

  1. ${H NO _3}$

  2. $HCl$

  3. ${Cl _2}$

  4. ${H _2SO _4}$

Show answer
Correct Option: B
Explanation:

When sodium bicarbonate reacts with $HCl$, chlorine binds with sodium and forms sodium chloride and bicarbonate ion binds with hydrogen ion of $HCl$ and forms carbonic acid. The carbonic acid further dissociates to water and carbon dioxide.

Slaked lime reacts with chlorine to give:

chemistry substances in common use chemical from common salt compounds of carbon some useful compounds in everyday life

  1. $CaCl _2$

  2. $CaO$

  3. $Ca(OCl) _2$

  4. $CaCO _3$

Show answer
Correct Option: C
Explanation:

Slaked lime reacts with chlorine to give bleaching powder.


$Ca(OH) _2  + Cl _2 \rightarrow CaOCl _2 + H _2O$

The solution of bleaching powder in water is always a clear solution.

chemistry substances in common use chemical from common salt compounds of carbon some useful compounds in everyday life

  1. True

  2. False

Show answer
Correct Option: A
Explanation:

Bleaching powder is known as calcium hypochlorite. It is marketed as bleach powder. It is white solid although commercial samples appear yellow. It is not highly soluble in water and is used in soft to medium hard water. It has two forms dry and hydrated.

The molecular formula of Baking soda is:

chemistry substances in common use chemical from common salt compounds of carbon some useful compounds in everyday life

  1. $NaHCO _3$

  2. $NaHCO _3.6H _2O$

  3. $Na _2CO _3$

  4. $Na _2CO _3.10H _2O$

Show answer
Correct Option: A
Explanation:

Baking soda is commonly known as sodium bicarbonate $ NaHC{ O } _{ 3 } $ used for cooking purposes.

Bleaching powder is effective with cold water, but ineffective with hot water. This is because of:

chemistry substances in common use chemical from common salt compounds of carbon some useful compounds in everyday life

  1. oxidation of chloride radical

  2. reduction of chloride radical

  3. reduction of hypochlorite radical

  4. hydrolysis of hypochlorite radical

Show answer
Correct Option: C
Explanation:

Bleaching action takes place due to the hypochlorite radical [$ClO^{-}$].

But when used in hot water, hot water favours reduction of the hypochlorite radical as a result of which bleaching powder is ineffective with hot water.
Generally, Bleaching powder is used as a disinfectant widely.