Q: \$CO_{2}\$ is gas, while \$SiO_{2}\$ is a solid at room temperatue. State a reason for it.

\$CO_2\$ consists of individual molecules with one central carbon atom double bonded to two oxygen atoms. Silicon does not form double bonds with oxygen.\$CO_2\$ is gas but \$SiO_2\$ is solid because the \$SiO_2\$ is in giant molecular structure but the \$CO_2\$ is simple molecular structure.Because of this reason \$CO_2\$ is gas but \$SiO_2\$ is solid.

Question 1

Why does carbon form such a large number of compounds?

Accepted Answer

Carbon is the only element that can form so many different compounds because each carbon atom can form four chemical bonds to other atoms and because the carbon atom is just the right, small size to fit in comfortably as parts of very large molecules. This property is called the catenation

Question 2

Explain why carbon forms compound mainly by covalent bonds. Explain in brief two main reasons for carbon forming a large number of compounds. Why does carbon form strong bonds with most other elements?

Accepted Answer

Carbon has 4 electrons in its outermost shell, and needs to gain or loss 4 electrons to attain nobel gas configuration. Losing or gaining 4 electrons is not possible due to energy considerations, hence it shares electrons to form covalent bonds.Two reasons for large number of carbon compounds:1) Catenation: The unique ability of carbon to form bonds with other atoms of carbon giving rise to long chains of different types of compounds.2) Tetravalency: since carbon has a valency of 4, it is capable of bonding with four other atoms of Carbon or atoms of elements like oxygen, hydrogen, nitrogen, sulphur, chlorine etc.Carbon forms strong bonds with most other elements because of its small size which enables the nucleus to hold on to the shared pairs of electrons strongly.

Question 3

What are the two properties of carbon which lead to the formation of a large number of carbon compounds?

Accepted Answer

Catenation (self linking of carbon atoms to form long chains) and Tetravalency are the two properties of carbon which lead to the formation of a large number of carbon compounds.

Question 4

$CO_{2}$ is gas, while $SiO_{2}$ is a solid at room temperatue. State a reason for it.

Accepted Answer

$CO_2$ consists of individual molecules with one central carbon atom double bonded to two oxygen atoms. Silicon does not form double bonds with oxygen.$CO_2$ is gas but $SiO_2$ is solid because the $SiO_2$ is in giant molecular structure but the $CO_2$ is simple molecular structure.Because of this reason $CO_2$ is gas but $SiO_2$ is solid.

Question 5

Catenation is the ability of an atom to form bonds with other atoms of the same element. It is exhibited by both carbon and silicon. Compare the ability of catenation of the two elements. Give reasons.

Accepted Answer

Both carbon and silicon show the ability of catenation. But compounds made by silicon are reactive and less stable. On the other hand, bonds formed by carbon are very strong and hence organic compounds are more stable than silicon compounds. It can be said that carbon shows better catenation ability than silicon.

Question 6

The compound that will react most readily with gaseous bromine has the formula is:

Accepted Answer

The compound that will react most readily with gaseous bromine has the formula $C_3H_6$.Unsymmetrical alkenes generally are more reactive than the symmetrical alkenes, alkynes and alkanes. That is why, propene is more reactive than the other given compounds. Hence, option C is correct.

Question 7

Arrange the group 14 elements in the order of decreasing ionisation energies.

Accepted Answer

As we move down the group, the ionisation energy decreases, due to increase in atomic size, thereby, increasing the distance of the electrons from the nucleus. The first ionisation energy of lead is slightly higher than that of tin. The reason is due to lanthanide contraction. The atomic size of tin and lead are very close, and hence, the charge density is more in case of lead, due to more charge. Due to higher charge density, the outer electrons are attracted more by the nucleus in lead and hence, the ionisation energy is more in the case of lead.

Question 8

Define: Catenation

Accepted Answer

The large number of organic compounds is due to the ability of carbon atom to form long chains with other carbon atoms through the sharing of electrons. This unique property of carbon is known as catenation.Carbon atoms can form long chains by sharing their valence electrons with other carbon atoms.

Question 9

Which of the following is not a Lewis acid?

Accepted Answer

Lewis Acid is one that accepts electrons. So, usually a compound with positive charge would be acid. Also, a compound with empty orbitals. Lewis Base is one that donates electrons. So, usually a compound with negative charge would be considered base. Also, a compound with lone pairs. $SiF_4$,$FeCl_3$ and $BF_3$ are lewis acids becuase all these compounds are having vacant orbitals to accept electon pairs$C_2H_2$ is not a lewis acid.It's a Lewis base, as it can use a pair of electrons from the pi bond to donate to a Lewis acid.Hence option D is correct.

Question 10

What are the two properties of carbon which lead to the formation of a large number?

Accepted Answer

The two properties that give rise to carbon to form a large number of compounds are:1) Catenation: It is the ability to form bonds with other carbon atoms.2) Tetravalency: Due to 4 valency of carbon, it is capable of bonding with four other atoms.

Revise with Concepts

Group 14 - Atomic Properties

Group 14 - Physical and Chemical Properties

Carbon - Trends and Anomalous Behaviour

Quick Summary With Stories

Group 14 - Atomic Properties

Group 14 - Physical and Chemical Properties - II

Group 14 - Physical and Chemical Properties - I

Carbon - Anomalous Behaviour

Why does carbon form such a large number of compounds?

Explain why carbon forms compound mainly by covalent bonds. Explain in brief two main reasons for carbon forming a large number of compounds. Why does carbon form strong bonds with most other elements?

What are the two properties of carbon which lead to the formation of a large number of carbon compounds?

$C O_{2}$ is gas, while $S i O_{2}$ is a solid at room temperatue. State a reason for it.

Catenation is the ability of an atom to form bonds with other atoms of the same element. It is exhibited by both carbon and silicon. Compare the ability of catenation of the two elements. Give reasons.

The compound that will react most readily with gaseous bromine has the formula is:

Arrange the group 14 elements in the order of decreasing ionisation energies.

Define: Catenation

Which of the following is not a Lewis acid?

What are the two properties of carbon which lead to the formation of a large number?

Revise with Concepts

Group 14 - Atomic Properties

Group 14 - Physical and Chemical Properties

Carbon - Trends and Anomalous Behaviour

Quick Summary With Stories

Group 14 - Atomic Properties

Group 14 - Physical and Chemical Properties - II

Group 14 - Physical and Chemical Properties - I

Carbon - Anomalous Behaviour

Why does carbon form such a large number of compounds?

Explain why carbon forms compound mainly by covalent bonds. Explain in brief two main reasons for carbon forming a large number of compounds. Why does carbon form strong bonds with most other elements?

What are the two properties of carbon which lead to the formation of a large number of carbon compounds?

CO2​ is gas, while SiO2​ is a solid at room temperatue. State a reason for it.

Catenation is the ability of an atom to form bonds with other atoms of the same element. It is exhibited by both carbon and silicon. Compare the ability of catenation of the two elements. Give reasons.

The compound that will react most readily with gaseous bromine has the formula is:

Arrange the group 14 elements in the order of decreasing ionisation energies.

Define: Catenation

Which of the following is not a Lewis acid?

What are the two properties of carbon which lead to the formation of a large number?

$C O_{2}$ is gas, while $S i O_{2}$ is a solid at room temperatue. State a reason for it.