A new penny has a mass of 2.49 g and a volume of 0.349 cm3. Is the penny made of pure copper?

What is the mass number of an oxygen atom with nine neutrons in its nucleus? (a) 8 (b) 9 (c) 17 (d) 16 (e) 18

An animal skeleton has a carbon-14 decay rate of 13.1 disintegrations per minute per gram of carbon. When did the animal die? (Assume that living organisms have a carbon-14 decay rate of 15.

Which mountain range formed as a result of plate motion around the Ring of Fire?

3. How many atoms are in 1.75 moles of CHCl 3?

Could a prokaryote have tissue, organs, and organ system?

Which of the following is an example of a molecule? F C Al O2

Organize the items listed into the proper sequence of events for gas exchange. a: O2 is transported to cells by circulatory system. b: O2 is drawn into the lungs during inhalation. c: Cells use O2 and generate CO2. d: CO2 is exhaled.

Research about the reaction of baking soda and vinegar

What mass (in mg) does 2.63 moles of nickel have? 3.56 * 105 mg 1.54 * 105 mg 2.23 * 104 mg 129 mg?

Given the propane molecule C3H8 (g) ! a) What is the balanced equation for the combustion of propane in O2? (20 pts.) b) What is the standard enthalpy change ΔH0 for the reaction at 25°C? (20 pts.