The mass number is the number of protons plus the number of neutrons. Since there are 16 neutrons, there are 14 protons. This also corresponds to the atomic number, so this atom's atomic number is 14 which is also Silicon
The purpose of the uninoculated control tubes used in this test is that two uninoculated control tubes are needed to show the results of the medium in both aerobic and anaerobic environments. It is used to show it is sterile and also as a color comparison, used also to show that the medium remains green under both conditions.
Meiosis 1 is the reductional division ! so after telophase 1 , cytokinesis takes place and two haploid cells are formed !
I think this is what you mean:
H H H H
H-C-C-C-C-H
H H H H
OR
<span>CH3CH2CH2CH3
</span>
If not, clarify and I will be happy to help.