Elements

Question 1

One isotope of sodium has 11 protons and 7 neutrons. What is the mass number of this isotope?

Revolt · Accepted Answer

18

Question 2

The chemical symbol for the element calcium is Ca. What would be the symbol representing calcium atoms that have lost two electrons?

Revolt · Accepted Answer

Ca+2

Question 3

Which describes an atom that has fewer neutrons than protons and more electrons than protons?

Revolt · Accepted Answer

negative ion

Question 4

Which are different forms of an element that have different numbers of neutrons?

Revolt · Accepted Answer

isotopes

Question 5

What is the number at the end of an isotope’s name?

Revolt · Accepted Answer

mass number

Question 6

The simple model below is a neutral magnesium (Mg) atom with the element’s most common mass number.

Revolt · Accepted Answer

It must lose two electrons and become an ion.

Question 7

If we have a sample of silicon (Si) atoms that has 14 protons, 14 electrons, and 18 neutrons

Revolt · Accepted Answer

silicon-32

Question 8

The model below shows a calcium atom.

Revolt · Accepted Answer

8

Question 9

A potassium atom (atomic number 19) loses an electron while forming a bond with another atom.

Revolt · Accepted Answer

It is a positive ion that has one less valence electron than a neutral potassium atom.

Question 10

Uranium is an element that is often used in nuclear power plants. Uranium atoms are very large, and the substance can be dangerous if it is not carefully contained.

Revolt · Accepted Answer

They each have the same number of protons.

Elements Answers

More from this Course

TRY EDGENUITY HACKS