Answer:
B
Explanation:
Particles in a solid have fixed locations in a volume that does not change. Solids have a definite volume and shape because particles in a solid vibrate around fixed locations.
By circle fraction additional number for the number
Isotopes are chemical elements with same atomic number (Z), but different mass number (different number of neutrons).
Hydrogen is an element with atomic number 1. It has three isotopes:
1) protium (₁¹H), with mass number 1 (no neutrons).
2) deuterium (₁²H), with mass number 2 (one neutrons, n° = 2 -1, n° = 1).
3) tritium (₁³H), with mass number 3 (two neutrons, n° = 3 -1, n° = 2).