- Using the choices below, which is the complete symbol for the isotope that has the following subatomic particles: 19 protons, 21 neutrons, and 18 electrons.
C.
D.
E.
A.
40 -1
B.
40
21
iR-1
33K+1 4.K+1
izArt1
b. B
A
d. D
e. E
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c.
a.

The elements in nature have several types of isotopes

Isotopes are atoms whose no-atom has the same number of protons while still having a different number of neutrons.

So Isotopes are elements that have the same Atomic Number (Proton)

The element has : 19 protons, 21 neutrons, and 18 electrons.

atomic mass = protons+neutrons = 19+21=40

atomic number=number of protons=19

charge of elements = protons-electrons = 19-18=+1

The element in the periodic system having the atomic number 19 is K

So symbol of element

acid rain does not usually kill trees directly. instead, it is more likely to weaken the trees by damaging their leaves, limiting the nutrients available to them, or poisoning them with toxic substances slowly released from the soil. the main atmospheric pollutants that affect trees are nitrates and sulphates.

20 drops hope this