Elements Answers

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

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

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

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

The model below shows a carbide ion.

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.

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

The model below shows a calcium atom.

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

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