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3 years ago

For question #12, use the following picture: 12. What element is this? How do you know?

Chemistry

2 answers:

labwork [276]3 years ago

8 0

Answer: The element shown in the image is Helium (He).

Explanation: We are given a image of an atom having protons, neutrons and electrons.

Number of protons as shown in image = 2

Number of neutrons as shown in image = 2

Number of electron as shown in image = 2

Atomic number = Number of protons = Number of electrons

Atomic number of the element = 2

Atomic Mass = Number of protons + Number of neutrons

Atomic mass = 2 + 2 = 4

The element having Atomic number = 2 and mass number = 4 is Helium.

Element = $^4_2\textrm{He}$

morpeh [17]3 years ago

3 0

I believe the element is Helium. I know this because an atom of helium has an atomic number of 2, meaning it has 2 protons. Because it is an atom of helium and not an ion of helium it also possess the same number of electrons as well which is 2.

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