Why does air not have a definite formula?

A teniss ball has more mass than a gold ball because

An occuled front moves over farmland that has been experiencing drought conditions. What change in weather likely bring? A. more dry air and snunny skys B. violent, short-lived thunderstorms C. an extented period of rain D. gray skies, but no rain

A stack of books are sitting on the table. Which force is pulling it down? A. Buoyant force B. Pressure force C. Gravitational force

Which formula represents a molecule with the most polar bond? a. CO b. NO c. HI d. HCI

What type of macromolecule carries out catalysis in biological systems? A) proteins called enzymes B) carbohydrates called starches C) lipids called steroids D) nucleic acids called DNA E) carbohydrates called sugars

Much of life on Earth is based in aquatic biomes. What property of water allows life to survive in liquid water?

A neutral atom of beryllium (Be) has an average mass of 9 amu and 4 electrons. How many neutrons does it have? 13 9 5 4

Calculate the maximum mass of carbon dioxide that could be obtained by adding excess hydrochloric acid to 15 g of calcium carbonate.

True or false: during dry weather, the water level in a small pond drops because of runoff.

Bradley hit a baseball with a bat. The baseball then hit a window and caused the window to break. Where did the energy that broke the window come from?