A way to explain it is that back then all the continents were together but soon after drifted apart the were in the same place sort of put they drifted apart so that's sorta what happened. Hope that helps a little
Answer:
a. BH₃
Explanation:
According to the octet rules, atoms reach stability when are surrounded by eight electrons in their valence shell when they combine to form a chemical compound.
From the options, the only compound in which the central atom does not meet the octet rules is BH₃. The central atom is boron (B), which has 3 electrons in its valence shell. When B is combined with hydrogen (H), 3 electrons from the 3 atoms of H are added. The total amount of electrons is 6, fewer than 8 electrons needed to meet the rule.
hope this helps
Answer:
Give any two application for isotopes
Isotopes of iodine are used for radiotherapy in treatment of hyperthyroidism, cancer, etc.
Uranium, Radium, Polonium isotopes are used in atomic reactors.
Cobalt isotopes are used for irradiation of food products.