00:01
Okay, for the set of questions, we are given an element with atomic mass of a hundred eighty -nine and atomic number of 74.
00:09
So, question a, as for the net electrical charge of the nucleus, we know that nucleus is comprised of neutrons and protons, and neutrons has no charge, while the protons has positive charge.
00:24
So the net electrical charge of the nucleus is equal to the total.
00:30
Charge of the protons in there.
00:33
So this is equals to the number of protons multiplied by the charge of one proton.
00:41
And note that the number of protons is equals to the atomic number.
00:46
So solving, we have 74 multiplied by the charge of one proton, which is 1 .6 times 10, raised to negative 19.
00:53
Then we can find the total electrical charge of the nucleus is 1 .184.
01:02
Times 10 raised negative 17, hulu.
01:09
Next, b, ask for the number of neutrons.
01:14
So the number of neutrons is given by this...