The set of all sets that are not members of themselves. This contradiction is Russell's paradox.
Answer:
Gas is a state of matter that has no fixed shape and no fixed volume.
In addition to solids and liquids, gases are also a physical state in which matter can occur. All gases have weight. Unlike solids and liquids, gases will occupy the entire container that encloses them.
matter is "anything that has mass and volume (occupies space)
<em>Gases have mass. The space between gas particles is empty. Gases can be formed as products in chemical reactions. Gas particles can form bonds between them under certain conditions</em>
<em> Gases have volume which isn't fixed </em>(no fixed volume)<em> and no fixed shape. Gases expand to fill the space available. They can also be compressed into a very small space.</em>
Explanation:
Answer:

Explanation:
In all atoms, the number of protons = number of electrons, as a result the atom is neutral. Losing or gaining electrons will make the atom electrically charged and we call an electrically charged atom an ion.
Ca 2+ would be the symbol because losing two negative electrons makes calcium's nucleus more positive by two protons.