Elements Answers

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

The model below shows a calcium atom.

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.

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

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

All large radioactive atoms decay into smaller atoms by releasing alpha particles. Each alpha particle has 2 protons, 2 neutrons, and 0 electrons. The table below describes several neutral, low-mass atoms.

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

All atoms of the element potassium have 19 protons. One of the most stable types of potassium atoms has the mass number 39.

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

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