Which is an observation?

Which of the following diagrams represents a solution?

Match the definition with the state of matter.

How many valence electrons are in an atom of magnesium in the ground state?

One isotope of carbon has the atomic number 6 and the mass number 14.  An atom of this isotope contains:

What is the correct name for CuCl2?

A manganese (III) ion forms when a manganese atom:

Which is a noble gas?

Please provide the chemical formula that would form between the provided ions. Do not be concerned about using super- or subscript for your answer.  Just insert any numbers that are necessary as normal-sized font. Combining Fe3+ and O2- would form the chemical compound:

How many valence electrons are in a carbon atom in the ground state?