Explanation

• Atoms of the same element with same protons but different neutrons are called isotopes.
• They have the same atomic number but different mass numbers.
• Isotopes show different physical properties but similar chemical behavior.
• Example: Hydrogen has Protium, Deuterium, and Tritium.

Last verified on 02-05-2026

Explanation

• Neon (Ne) has an atomic number 10
• Its electronic configuration is 2, 8
• The outermost shell (valence shell) contains 8 electrons
• This makes neon a stable noble gas

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Last updated by NS on 01 MAY 2026

Explanation

• Hydrogen (H2) and Argon is not a greenhouse gas.
• Greenhouse gases are gases that trap heat in Earth’s atmosphere and cause the Greenhouse Effect.

The main greenhouse gases are:

• Carbon dioxide (CO2)
• Methane (CH4)
• Nitrous oxide (N2O)
• Water vapor (H2O)
• Ozone (O3)
• Chlorofluorocarbons (CFCs)
• Hydrofluorocarbons (HFCs)
• Perfluorocarbons (PFCs)

Last verified on 01-05-2026

Explanation

• The chemical name of chalk is Calcium carbonate.
• Its chemical formula is CaCO₃.
• It is a soft, white mineral.
• Commonly used in blackboard chalk and limestone.
• Found naturally in rocks and marine shells.

Last verified on 30-04-2026

Explanation

• Evaporation is the process of liquid changing into vapor.
• During this process, heat is absorbed from the surroundings.
• This causes a drop in temperature (cooling effect).
• That is why sweating cools the human body.
• Evaporation is a natural cooling phenomenon.

Last verified on 26-04-2026