Which radiation is the most penetrating? MCQ with Answer and Explanation

Explanation:
Diamond has a rigid 3D covalent network, making it the hardest natural material. It does not conduct electricity (no free electrons). It is not layered (graphite is). It is used as an abrasive, not a lubricant.

Explanation:
In CaCO₃ decomposition, the oxidation states are: Ca (+2), C (+4), O (-2) in both reactant and products, so no change—not a redox reaction. The others involve changes: Zn(0→+2), Cu(+2→0) in B; Na(0→+1), Cl(0→-1) in C; C(-4→+4), O(0→-2) in D. Redox requires change in oxidation numbers.

Explanation:
Methyl orange is red in acidic (pH4.4). So yellow indicates pH above 4.4; could be neutral or basic.