ICSE Class 10 Chemistry Competency Focused Practice Questions Solution-Structural diagram

ICSE Class 10 Chemistry Competency Focused Practice Questions Solution:

V. Structural diagram: (1 Mark each)

Question 69. [Organic Chemistry]
Draw the structural diagram of the product obtained when ethene reacts with chlorine.

Answer:

Explanation: When ethene reacts with chlorine, the product formed is 1,2-dichloro ethane.

CH₂ = CH₂ + Cl₂ → ClCH₂ – CH₂Cl

Question 70. [Organic Chemistry]
An organic acid on cooling below 16.5°C crystallises out in the pure form, forming a
crystalline mass resembling ice. Draw the structural diagram of this carboxylic acid.

Answer:

ethanol-chemistry-competency-focused-practice-questions-solution

Explanation: Acetic acid or ethanoic acid on cooling below 16.5°C crystallises out in the pure form, forming a crystalline mass resembling ice. Therefore, it is also called glacial acetic acid.

Question 71. [Chemical Bonding]
Magnesium ribbon is added to dilute HCl. A gas is liberated along with the formation of
a compound. Draw an electron dot diagram to show the structure of the compound that
is formed.

Answer:

magnesium-chloride-electron-dot-structure

Explanation: The equation is as follows:

Mg + HCl → MgCl₂ + H₂

As MgCl₂ is an electrovalent compound, we will show the electron dot structure, where Magnesium donates two electrons and each chlorine accepts one electron to become stable.

Question 72. [Organic Chemistry]
Draw the chain Isomer for the following organic compound.

Answer:

Explanation: The structural diagram given in the question is of pentene. Its chain isomer is 3 methyl but-1-ene.

Question 73. [Chemical Bonding]
Calcium hydroxide dissolves in water and forms a positive ion and a negative ion. Draw
the structure of the negative ion.

Answer:

hydroxyl-ion-chemistry-competency-focused-practice-questions-solution

Explanation: Calcium hydroxide contains Ca²⁺ and OH^– ions: this is two positive charges and one negative charge. Hence, we will have to draw the structure of hydroxyl ion.

Question 74. [Organic Chemistry]
Draw the structure of the following organic compounds:
2 – methyl butane

Answer:

Explanation: 2 – methyl butane will have 4 carbon atoms in a row and one carbon atom will be bonded with second carbon atom to make methyl.

Question 75. [Chemical Bonding]
The equation given above represents the molecule formation of element X. Fill in the
box with the electron dot structure of the molecule.

Answer:

triple-bond-chemistry-competency-focused-practice-questions-solution

Explanation: Atom X in the given question has 5 electrons in its valence shell. To attain stability, it needs 3 more electrons. Hence, both the atoms of X will make a triple covalent bond.

Question 76. [Chemical Bonding]
Draw an isomer of the given structure:

Answer:

n-butane-chemistry-competency-focused-practice-questions-solution

Explanation: The structure given in the question is 2 – methyl propane. This is an isomer of butane. Butane has 2 isomers: n-butane and iso-butane (2 – methyl propane).