<em>Answer: </em>John Dalton
Explanation: Democritus was a Greek philosopher (470-380 B.C.) who is the father of modern atomic thought. He proposed that matter could NOT be divided into smaller pieces forever. John Dalton created the very first atomic theory.
Answer: 1. Is2 2s2 2p3
2. Nitrogen
Explanation: The number of electron present In C = 6
But an extra electron is added since the charge on C is -1, this therefore makes the total electron 7.
1. By arrangement, the Electronic configuration is therefore;
Ans: 1s2 2s2 2p3
2. It is explained how C has 7 electrons, we can proceed then.
Neutral atom have atomic number of 7.
The element with atomic number of 7 is;
Ans: NITROGEN
Answer:
The atomic numbers of both are 54 while the mass numbers are 131 and 133 respectively.
Explanation:
- The number of protons = Atomic number. So, if the atom has 54 protons and it remained unchanged, then the two types of atoms of this element both have atomic numbers of 54.
- On the other hand, mass number is the sum of protons and neutrons
So, if type 1 has protons = 54 and neutrons = 77: mass number = 54 + 77 = 131
if Type 2 has protons = 54 and neutrons = 79: mass number = 54 + 77 = 133
(Since the possibility of atoms of the same element to have different mass numbers but the same atomic number is called isotopy). The two types of atoms with mass numbers 131 and 133 described are isotopes.
Answer:
is there a pic or anything?
