The <span>covalent bonds are predicted for each atom are :
</span>(a)F = 1
(b) Si = 4
(c) Br = 1
(d) O = 2
(e) P = 3
(f) S = 2
Answer:
5200 ppm
Explanation:
As per the definition, parts per million of a contaminant is a measure of the amount of mass of contaminant present per million amount of the solution. It is denoted by ppm.
Given in the question,
Water = 250 ml = 250 g
Lead = 1.30 g
So,
ppm of Lead =
=
= 5200 ppm
So, as calculated above, there is 5200 ppm of lead present in 250 ml of water.
Answer:
d) An atom of arsenic has one more valence electron and more electron shells than an atom of silicon, so the conductivity increases because the arsenic atom loses the electron.
Explanation:
This is an example of a n-type semiconductor. The additional electron introduced to the 'grid' of silicon atoms causes an increase in the conductivity of the silicon. This additional electron is introduced as arsenic loses its extra electron.
Answer:
True
Explanation:
Ex. People against vaccines tend to believe crazy theories over facts because they think they'll end up brainwashing them.