25. Describe the role of each of the following in predicting molecular geometries:
a. unshared electron pairs
b. double bonds

Which sentence about particles in matter is true? a. atoms are present in solids and liquids but not in gases. b. the particles of matter are in constant motion. c. the same kinds of atoms are found in different elements. d. when a solid changes to a liquid, the sizes of the particles change.

Acompound has a molecular weight of 12.124 atomic mass units and the empirical formula c3h40. what is the molecular formula of the compound?

How many grams of mgbr2 are needed to produce 75g or metal?