Chemistry Periodic Table

Question

The image shows the representation of an unknown element in the periodic table.

Answer Choices:

Based on the representation, which of the following statements about the element is true? (3 points)

	The combined number of protons plus electrons is 9.
	The number of neutrons in an atom of the element is 10.
	The combined mass of neutrons and electrons is 18.9984.
	The sum of the masses of protons and electrons is 18.9984.

Answer 1

There are 10 neutrons in this atom. To find the number of neutrons, you subtract the number of protons from the atomic mass number. 19 - 9 = 10

The number of protons and the number of electrons are the same if the atom is neutral (no charge).

The number of protons and the number of electrons are different if the atom is charged. If there are more protons than electrons, then the atom has a cation (positive ion/charge). If there are more electrons than protons, then the atom has an anion (negative ion/charge).

In this case, Statements #2 and 3 are true based on the provided explanation.

Answer 2

Hello, Delyla,

The Periodic Table Information for "Symbol" has a lot of information. I summarized the reasoning in a table that answers the questions. However, I can't seem to get the table to fit in the space allowed by Wyzant. I uploaded it to a Google Sheets that you can access:

https://docs.google.com/spreadsheets/d/1L3i7kCGCzaKn3lheYHO4o4d9HE7CRirpSEi97Rj-8L4/edit?usp=sharing

Symbol's periodic table diagram shows the atomic number (9) in the top right, and it's atomic mass on the bottom left. These two numbers are all you need to answer the questions.

I hope this helps,

Bob