Washing soda (Na₂CO₃·10H₂O) is obtained from sodium carbonate by: MCQ with Answer and Explanation

Explanation:
Alpha rays consist of ⁴₂He²⁺ particles (2 protons + 2 neutrons). They have low penetration but high ionization power.

Explanation:
Natural gas is primarily methane (CH₄), typically 70-90%, along with small amounts of ethane, propane, butane, and other hydrocarbons. It is a fossil fuel formed from the remains of ancient marine organisms. CNG (compressed natural gas) is methane stored at high pressure. LPG (liquefied petroleum gas) mainly contains propane and butane. Methane has the highest calorific value among the given options per unit mass.

Explanation:
Fluorine is the most electronegative element (Pauling scale 3.98). Electronegativity increases across a period and decreases down a group. Hence F > O > Cl > N.