Tag: compounds of carbon

Questions Related to compounds of carbon

The pair whose both species are used in antacid medicinal preparation is

  1. $NaHCO _3$ and $Mg(OH) _2 $

  2. $Na _2CO _3$ and $Ca(HCO _3) _2 $

  3. $Ca(HCO _3) _2$ and $Mg(OH) _2 $

  4. $Ca(OH) _2$ and $NaHCO _3$


Correct Option: A
Explanation:

Milk of magnesia is an aqueous suspension of magnesium hydroxide $[Mg(OH) _2]$ used to treat acid indigestion.
Also sodium bicarbonate is used for antacid 
medicinal preparation.

When we add a pinch of sodium hydrogen carbonate in a flask containing ethanoic acid a reaction takes place. What will be the observation when we carry out the reaction?

  1. Milky solution

  2. Bubble formation

  3. Solution turns red

  4. Brisk effervescence


Correct Option: D
Explanation:
Two main observations during the reaction are:
(i) Brisk effervescence
(ii) Sodium acetate is formed

Chemical equation for the reaction is:

$2CH _3COOH + 2NaHCO _3 \to 2CH _3COONa + 2CO _2 + 2H _2O$


Option D is correct.

'Sodium bicarbonate solution has $pH$ less than 7.'
State True or False:

  1. True

  2. False

  3. Cannot be determined

  4. None of the above


Correct Option: B
Explanation:

Sodium bicarbonate is amphoteric, reacting with acids and bases. It reacts violently with acids, releasing CO2 gas as a reaction product. Because of $NaHCO _3$ is a weak base the pH value should be greater than 7.

Reaction with sulfuric acid: 
$2 NaHCO _3 + H _2SO _4 \rightarrow Na _2SO _4 + 2 H _2O + 2 CO _2$ 

With sodium hydroxide: 
$NaHCO _3 + NaOH \rightarrow Na _2CO _3 + H _2O$

Hence, statement is false.

RCOOH decomposes $NaHCO 3$ to liberate $ CO _2$ which comes from_____:

  1. $NaOHCO _{3}$

  2. $NaHCO _{3}$

  3. $NaHCO _{2}$

  4. $NaHCO$


Correct Option: B
Explanation:

RCOOH decomposes $NaHCO _3$ to liberate $CO _2 $ which comes from $NaHCO _3$.
$NaHCO _3 + RCOOH \rightarrow RCOONa + H _2O + CO _2$

$NaHCO _3$ represent the formula of which one of the following? 

  1. Sodium carbonate

  2. Baking soda

  3. Sodium acetate

  4. Washing soda


Correct Option: B
Explanation:

${ NaHCO } _{ 3 }$ is sodium bicarbonate or known as sodium hydrogen carbonate. Sodium bicarbonate is a white solid that appears as fine powder. It has a slightly salty, alkaline taste resembling that of sodium carbonate(washing soda). It is also known as baking soda or cooking soda. 

The balanced equations for : "Carbon dioxide is passed through a concentrated aqueous solution of sodium chloride saturated with ammonia".

  1. $NaCl + NH _4OH + CO _2\rightarrow NH _4Cl +NaHCO _3$

  2. $2NaCl + NH _4OH + CO _2\rightarrow NH _4Cl +2NaHCO _3$

  3. $NaCl + NH _4OH + CO _2\rightarrow NH _4CO +NaHCl _3$

  4. $NaCl + NH _4OH + CO _2\rightarrow NH _3 +NaCl+H _2CO _3$


Correct Option: A
Explanation:

$NaCl + NH _4OH + CO _2\rightarrow NH _4Cl +NaHCO _3$ 

Sodium bicarbonate is formed. This reaction is used in the Solvay process for the manufacture of sodium carbonate.

A milkman adds a very small amount of baking soda to fresh milk. The pH will :

  1. increase

  2. decrease

  3. same as milk

  4. none of these


Correct Option: A
Explanation:

Baking soda is mild base, so when it is added to milk the pH of the milk slightly increases towords basic value.

Baking powder contains baking soda and : 

  1. potassium hydrogen tartarate

  2. calcium bicarbonate

  3. sodium carbonate

  4. vinegar


Correct Option: A
Explanation:

Baking powder is dry chemical leavening agent a mixture of carbonate or bicarbonate and a weak acid. A typical acid in such formulations is cream of tartar derivative of tartaric acid. Commercially it is sodium bicarbonate.

Sodium sesquicarbonate is 

  1. $\displaystyle Na _{2}CO _{3}NaHCO _{3}$

  2. a double salt

  3. trisodium hydrogen discrabonate

  4. water softner


Correct Option: A,B,C,D
Explanation:
Sodium sesquicarbonate (Systematic name trisodium hydrogendicarbonate) $Na _3H(CO _3) _2$ is a double salt of sodium bicarbonate and sodium carbonate($\displaystyle Na _{2}CO _{3}NaHCO _{3}$), and has a needle-like crystal structure. However, the term is also applied to an equimolar mixture of those two salts, with whatever water of hydration the sodium carbonate includes, supplied as a powder.
odium sesquicarbonate is used in bath salts, swimming pools, as an alkalinity source for water treatment.
Hence options A,B,C & D are correct.

The element which is not common between the compounds called baking soda and soda ash is:

  1. nitrogen

  2. hydrogen

  3. oxygen

  4. sulphur


Correct Option: B
Explanation:

Baking soda formula is $NaHCO _3$.

Soda ash formula is $Na _2CO _3$.
So, hydrogen atom $(H)$ is not common between the compounds of baking soda and soda ash.
So, the answer is $B$.