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Sublimation is the transition of a substance directly from the solid to the gas state, without passing through the liquid state. Familiar substances that sublime readily include iodine, dry ice, menthol, and camphor.

Atomic weight, also called relative atomic mass, ratio of the average mass of a chemical element's atoms to some standard.

The N shell is the fourth orbit with 32 max number of electrons using 2n\(^2\)

mass number, is the sum of the numbers of protons and neutrons present in the nucleus of an atom.

Avogadro's number is an absolute number: there are 6.022\times10\(^23\) elementary entities in 1 mole. helium has a molar mass of 4.0 grams per mole. So one mole of helium has a mass of 4.0 grams.

One mole of carbon dioxide molecules has a mass of 44.01 g, : 5 mole of carbon dioxide molecules has a mass of 220g

An atom nucleus is made up of protons and neutrons. An electron is a negatively charged subatomic particle that orbits the nucleus of an atom.

- Hydrolysis is any chemical reaction in which a molecule of water breaks one or more chemical bonds. -Salt hydrolysis is a reaction in which one of the ions from a salt reacts with water, forming either an acidic or basic solution.

Bohr Model is a planetary model in which the negatively charged electrons orbit a small, positively charged nucleus similar to the planets .

Hygroscopic substances are used to keep products dry or to remove water from an area. They are commonly used in desiccators Some common examples of hygroscopic substances include: Sodium chloride. Zinc chloride. Calcium chloride

The most abundant naturally occurring gas is Nitrogen (N2), which makes up about 78% of air. Oxygen (O2) is the second most abundant gas at about 21%. The inert gas Argon (Ar) is the third most abundant gas. Argon is the most abundant rare gas in the atmosphere. It is represented by the symbol Ar. The atomic number of Ar is 18.

The Group 7 elements are called the halogens. They are placed in the vertical column, second from the right, in the periodic table . Chlorine (17), bromine(35) and iodine(53) are the first three of the Group 7 elements.

- The enthalpy change associated with the removal of the first electron from an isolated gaseous atom. - Ionization enthalpy is the minimum amount of energy required to detach from an isolated gaseous atom the most loosely bound electron and turn it into a gaseous cation.

The actinide or actinoid series encompasses the 15 metallic chemical elements with atomic numbers from 89 to 103, actinium through lawrencium. The actinide series derives its name from the first element in the series, actinium.

Carbon dioxide, a colorless gas having a faint sharp odor and a sour taste. It is a greenhouse gas. Global warming occurs when carbon dioxide (CO2) and other air pollutants collect in the atmosphere and absorb sunlight and solar radiation that have bounced off the earth’s surface. Normally this radiation would escape into space, but these pollutants, which can last for years to centuries in the atmosphere, trap the heat and cause the planet to get hotter. These heat-trapping pollutants—specifically carbon dioxide, methane, nitrous oxide, water vapor, and synthetic fluorinated gases—are known as greenhouse gases, and their impact is called GREENHOUSE EFFECT