- (a) isomerism
- (b) allotropy
- (c) catenation
- (d) crystallinity
Answer:
(b) allotropy
- (a) allotropy
- (b) isomerism
- (c) tetravalency
- (d) catenation
Answer:
(d) catenation
Carbon’s tetravalency also contributes significantly.
- (a) Polystyrene
- (b) PVC
- (c) Polypropylene
- (d) LDPE
Answer:
(c) Polypropylene
- (a) 2
- (b) 5
- (c) 6
- (d) 7
Answer:
(d) 7
Correction made:
Original answer incorrectly mentioned option (a).
- (a) diamond
- (b) fullerene
- (c) graphite
- (d) gas carbon
Answer:
(c) graphite
- (a) Forest
- (b) Wildlife
- (c) Environment
- (d) Human rights
Answer:
(c) Environment
- Antoine Lavoisier named carbon.
- Buckminster fullerene contains 60 carbon atoms.
- Compounds having same molecular formula but different structural formula are called isomers.
- Carbon disulphide is a suitable solvent for sulphur.
Correction made:
Original answer incorrectly mentioned allotropy.
- There are seven plastic resin codes.
| List I | List II |
|---|---|
| Alkyne | Triple bond |
| Andre Geim | Graphene |
| (C_{60}) | Bucky Ball |
| Thermocol | Polystyrene |
| Combustion | Oxidation |
| Graphite | Diamond |
|---|---|
| Each carbon forms 3 covalent bonds | Each carbon forms 4 covalent bonds |
| Soft and slippery | Extremely hard |
| Layered hexagonal structure | Tetrahedral 3D structure |
| Conducts electricity | Poor conductor of electricity |
| Opaque | Transparent |
Correction made:
Diamond conducts heat well though it is electrical insulator.
(i) n-Butane
(ii) Iso-butane (2-Methylpropane)
Answer:
Carbon has four valence electrons.
Losing or gaining four electrons requires very high energy.
Hence carbon attains stability by sharing electrons and forms covalent compounds.
Answer:
Property by which an element exists in more than one form in same physical state is called allotropy.
Examples:
- Diamond
- Graphite
- Fullerene
Answer:
- Cause environmental pollution
- Block drains and water bodies
- Harm animals and marine life
- Produce toxic chemicals
- Non-biodegradable
Examples:
- Plastic carry bags
- Cups
- Straws
- Food wrappers
Answer:
Catenation is property by which atoms of same element link together through covalent bonds.
Carbon and Catenation
- Carbon atoms bond with one another repeatedly.
- They form:
- straight chains
- branched chains
- ring structures
- This leads to enormous number of organic compounds.
Examples:
- Starch
- Cellulose
- Hydrocarbons
# (i) Oxidation / Combustion
Carbon reacts with oxygen.
Incomplete combustion:
Methane Combustion
# (ii) Reaction with Steam
Mixture formed is called:
Water Gas
# (iii) Reaction with Sulphur
(Carbon disulphide)
# (iv) Reaction with Metals
Carbon forms carbides.
Example:
(Tungsten carbide)
Correction made:
Spelling corrected from “Tungesten”.
Resin Code 2 — HDPE
- Strong
- Recyclable
- Safer plastic
Resin Code 4 — LDPE
- Flexible
- Used in carry bags
Resin Code 5 — PP (Polypropylene)
- Heat resistant
- Safer for food storage
Answer:
Carbon readily forms compounds due to:
- Catenation
- Tetravalency
- Multiple bonding
- Isomerism
- Allotropy
Hence carbon mainly occurs in combined form.
Answer:
Incomplete combustion forms carbon monoxide.
Carbon monoxide:
- binds with haemoglobin
- reduces oxygen transport
- may cause suffocation and death
# Formation of Dioxins
Dioxins form during:
- burning plastics
- industrial processes
- waste incineration
Especially when chlorine-containing materials burn.
# Linked Plastic
PVC (Polyvinyl Chloride)
# Harmful Effects
- Cancer
- Hormonal imbalance
- Immune suppression
- Reproductive disorders
- Developmental defects
Answer:
She should buy bottle with:
Resin Code 5
(Polypropylene)
Reason
- Safer plastic
- Heat resistant
- Less toxic
Why Avoid Others?
Resin Code 1
Single-use plastic.
Resin Code 3
PVC — highly toxic.
Resin Code 7
Contains polycarbonate and BPA-related plastics.
Organic and Inorganic Compounds
| Organic | Inorganic |
|---|---|
| Propane | (CO_2) |
| Kerosene | CO |
| Coconut oil | MgO |
| Perfume | (Na_2CO_3) |
| Alcohol | (CaCO_3) |
| Petrol | HCN |
| LPG |
Correction made:
PVC is organic polymer, not inorganic.
Fullerene and Football
Observation:
Football resembles Buckminster fullerene structure.
Contains:
- 12 pentagons
- 20 hexagons
Similar arrangement exists in:
(Buckminster fullerene)
# Important Summary
Allotropy
Different forms of same element.
Examples:
- Diamond
- Graphite
- Fullerene
Catenation
Self-linking property of carbon.
Isomerism
Same molecular formula, different structures.
Graphene
Single layer of graphite.
Fullerene
Spherical carbon molecule.
Safer Plastics
Resin codes:
- 2
- 4
- 5
Harmful Plastics
Resin codes:
- 3
- 6
- 7
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