Many types of living cells, including human skin cells, can be damaged or killed if exposed to ultraviolet light from the sun. how does the earth's atmosphere protect organisms on the surface from exposure to ultraviolet light? a. oxygen in the atmosphere scatters most ultraviolet light from the sun b. carbon dioxide in the atmosphere absorbs most infrared light from the sun c. ozone in the atmosphere absorbs most ultraviolet light from the sun. d. gaseous water reflects most ultraviolet light from the sun back into space

Every compound can be represented by a chemical formula. a chemical formula is the set of symbols showing the elements that make up a compound and their proportions. water’s chemical formula is h 2 2 o. that means a molecule of water contains two atoms of hydrogen and one atom of oxygen chemically bonded. a molecule is a group of two or more atoms bonded together. molecules can range in size from two to thousands of atoms. a molecule of a compound is the smallest unit of that compound. every molecule of water has all the physical and chemical properties of water. that’s because every molecule of water is made of the same elements in the same proportions: two hydrogen atoms and one oxygen! which of the following is a true statement? a every molecule of the same compound will have different properties. b every molecule of a compound has the same proportion of elements. c molecules can be physically separated into smaller units of a compound. d molecules cannot be represented by chemical formulae.

In which situations is the principle of cross-cutting relationship useful in determining relative age?

We can be sure that a mole of table sugar and a mole of vitamin c are equal in their 1) mass in daltons. 2) mass in grams. 3) number of molecules. 4) number of atoms. 5) volume.