3. What do we call atoms of the same elements with different mass numbers?

Two liters of a perfect gas are at 0>c and 1 atm. if the gas is nitrogen, n2, determine the number of molecules.

You place a balloon in a closed vacuum chamber at standard temperature and pressure (STP). You decrease the pressure in the chamber by half but keep the temperature constant. What happens to the volume of the balloon? a. It stays the same volume. b.

Hurricanes can be very destructive, bringing tornadoes, flooding, strong winds, and storm surges to the land areas they come in contact with.

How many moles of Lithium Fluoride will you need to add to 250.0 mL of water to make a 5.00 M solution?

When the molecules of gases are heated, the average kinetic energy of the molecules increases, a. True b. False?

What moves in or out of a substance during a change of state?

2.5 moles of sodium chloride is dissolved to make 0.050 liters of solution

2. The minimized structure of phenacetin is planar, and the chemical shifts of the aromatic protons in the NMR spectrum can be rationalized by electron delocalization.

Altering the pressure of a system can affect the rate of a chemical reaction. true false

What does ice cream melt on a hot day which type of thermal energy transfer does this melting represents