How does the idea of a neutron help address the puzzles about the protons in the nucleus and the mass of atoms?

acid rain does not usually kill trees directly. instead, it is more likely to weaken the trees by damaging their leaves, limiting the nutrients available to them, or poisoning them with toxic substances slowly released from the soil. the main atmospheric pollutants that affect trees are nitrates and sulphates.

in the analysis of systems that involve fluid flow, we frequently encounter the combination of properties u and pv.

a electronegativity decreases beacuse the size of nucleus is bigger.