Tag: chemistry

Quizzes (490) Questions (9892)

Questions Related to chemistry

Multiple choice chemistry p- block elements-ii hydrogen chloride chlorine - 17 group p-block elements

The concentrated $HCl$ acid strongly fumes in_________.

  1. air

  2. water

  3. both

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

Concentrated hydrochloric acid fumes in the air forming acidic mists. Both the mist and the solution have a corrosive effect on human tissue with the potential to damage respiratory organs, eyes, skin and intestines.

Multiple choice chemistry p- block elements-ii hydrogen chloride chlorine - 17 group p-block elements

The boiling point of the hydrochloric acid varies with its concentration.

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Physical properties of $HCl$ acid such as boiling point and melting points, density and pH depend upon the concentration or molarity of $HCl$ in the aqueous solution. They range from those of water at very low conc. approaching 0% $HCl$ to values for fuming $HCl$ over 40% $HCl$.

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

Which of the following is not a use of baking soda?

  1. In medicines as antacid

  2. As a component of baking powder

  3. In removing permanent hardness of water

  4. In fire extinguishers
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Baking soda,$(NaHCO _3)$ also known as sodium bicarbonate, is widely used in baking. This is because it has leavening properties, meaning it causes dough to rise by producing carbon dioxide. Aside from cooking, baking soda has a variety of additional household uses and health benefits.

They are-
  • In medicines as antacid
  • As a component of baking powder
  • In fire extinguishers
  • Relieves insect bites
  • Relieves skin irritation
  • Air Freshener
  • Hence, option C is wrong about baking soda as it is not used in removing permanent hardness of water.

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

In Solvay ammonia process, sodium bicarbonate is precipitated due to :

  1. presence of $NH _3$
  2. reaction with $CO _2$

  3. reaction with brine solution

  4. reaction with NaOH
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

In Solvay process, sodium bicarbonate is precipitated due to common ion$(Na^+)$ effect provided by brine (concentrated NaCl Solution).

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

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

  1. Behaves as an acid in moist condition and decomposes $NaHCO _{3}$ to give $CO _{2}$
  2. Behave as a base in moist condition and gives $H _{3}PO _{4}$

  3. Behaves as binder

  4. Behaves as a filler
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The baking powder consists of sodium bicarbonate and calcium dihydrogen phosphate.In this process the ${ H } _{ 2 }{ PO } _{ 4 }$ acts as acid in the baking powder and then reacts with ${ NaHCO } _{ 3 }$  so that carbon dioxide that expands in the food items.When sufficient heat is given bond will breaks between  $Ca$ and ${ H } _{ 2 }{ PO } _{ 4 }$ and then reacts with 

$NaHC{ O } _{ 34 }$ and the carbon dioxide will be formed.

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

When sample of baking soda is strongly ignited in crucible it suffered loss in weight of  $3.1 g $  the mass of baking soda is- 

  1. $ 16.8 g $
  2. $ 8.4 g $
  3. $ 11.6 g $
  4. $4.2 g $
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
The reaction is:
$2NaHCO _3 \rightarrow Na _2CO _3+H _2O+CO _2$

The loss in weight is due to water and carbon dioxide.

$2$ moles $(2\times 84 g)$ of sodium bicarbonate gives $ 1$  mole $( 18  g)$ of water and $ 1$ mole of carbon dioxide $( 44 g)$.

Thus, decomposition of $ 168   g$ of sodium bicarbonate will result in loss in weight of $18+44=62g$

The loss in weight of $3.1$ g corresponds to $\dfrac{168}{62}\times 3.1=8.4g$ of sodium bicarbonate. 

Option B is correct.
Multiple choice chemistry substances in common use preparation, properties and uses of baking soda chemical from common salt compounds of carbon

Which of the following is known as fusion mixture?

  1. mixture of $Na _{2}CO _{3}+NaHCO _{3}$
  2. $Na _{2}CO _{3}+10H _{2}O$
  3. mixture of $K _{2}CO _{3}+Na _{2}CO _{3}$
  4. $NaHCO _{3}$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

A fusion mixture consists of a sodium salt and a potassium salt. Generally, mixture of potassium carbonate and sodium carbonate is used. It is called a fusion mixture because it is fused with a sample of organic compound to test for various groups.

Hence option C having both sodium carbonate and potassium carbonate is the correct answer.

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

Read the given statements and select the correct option:


Statement 1 :Backing soda does not taste sour.
Statement 2 :Bases are sour in taste while acids are bitter in taste.

  1. Both statements 1 and 2 are true statement 2 is correct explanation of statement 1.

  2. Both statements 1 and 2 are true both statement 2 is not the correct explanation of statement 1.

  3. Statements 1 is true and statement 2 is false

  4. Both statements 1 and 2 are false.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Baking soda,which has chemical name sodium bicarbonate $(NaHCO _3)$ is slightly basic in nature.Which means it tastes bitter as acid taste sour and bases taste bitter.

Statement 01: $NaHCO _3$ does not taste sour  is correct.
Statement 02: Acid taste bitter and bases taste sour is wrong.