A certain negative ion x_2 has its nucleus 18 neutrons and 18 electrons
Answers
Answer:
32
Explanation:
You know that this negative ion has a total of
18
electrons surrounding its nucleus.
As you know, the net charge of an ion is given by the difference that exists between the number of protons located inside its nucleus and the number of electrons surrounding its nucleus.
net charge = no. of protons
−
no. of electrons
You can use the fact that the ion has a
2
−
net charge to determine the number of protons located inside its nucleus.
no. of protons
=
(
2
−
)
+
18
=
18
−
2
=
16
So, you know that element
X
has
16
protons inside its nucleus, i.e. an atomic number,
Z
, equal to
16
.
The mass number of an atom,
A
, is given by the number of nucleons--protons and neutrons--located inside its nucleus
A
=
Z
+
no. of neutrons
This means that this particular isotope of
X
has
A
=
16
+
18
=
34
Now, in order to check whether or not this particular isotope is also the most abundant, you must grab a Periodic Table and look for the element that has
Z
=
16
.
You will find that element
X
is sulfur,
S
, and this particular isotope is sulfur-34,
34
S
.