D. To answer this question refer to the periodic table and think logically about it. Adding one proton increases the atomic number so you go along the row to Nitrogen. If you lose one neutron then the atomic mass decreases by 1 so 14-1 is 13.
First, we construct the reaction equation:
Na₂SO₃ + 2HCl → 2NaCl + SO₂ + H₂O
H₂SO₃ is formed as an intermediate but decomposes to water and SO₂ gas.
Various pieces of safety equipment are used in the lab to provide protection against injury. However, the lab safety equipment which is least likely to be used when proper eye goggles are being worn is the eye wash station. If this question has the same choices as the ones posted before, the answer is letter C. eye wash station.
There are several things that can help scientists evaluate which category something belongs to. The similarity in features is one of them. If two skulls looked alike, they were probably species of the same evolutionary category. For example say humans and monkeys rather than humans and dogs.
Similarly fossils have helped scientists categorise species. Study of the chromosomes (in cases with available chromosomes) can help scientists figure out a lot about the subjects and categorise them.