Calculate the change in energy requiredto convert 250. g of substance X from a gas at 121°C to a solid at - 49.0°C. Assume X has molar mass = 75.0 g/mol. Also, substance X has the following properties:

In general, if a reaction is spontaneous, the reactants possess more free energy than the products. TRUE FALSE

34.62 mL of a 0.1510 M barium hydroxide solution was needed to neutralize 50.0 mL of a hydrochloric acidsolution. What is the concentration of the original hydrochloric acid solution?

Gold has a density of about 20g/mL. If I had a 60g sample, it should have a volume of about ___mL.

Show the conversion factor from Patolbf/ft2is 0.02089.

Which reaction will most likely take place? Pt + FeCl3 Mn + CaO Li + ZnCO3 Cu + 2KNO3

A flask containing 155cm^3 of hydrogen was collected under a pressure of 22.5kPa. What pressure would have been required in order for the volume of the gas to have been 90.0 cm^3 at constant temperature?

Which change is most likely to occur when a molecule of H2 and a molecule of I2 collide with proper orientation and sufficient energy? 1. a chemical change, because a compound is formed 2. a chemical change, because an element is formed 3.

Which substance is a diatomic molecule? a. he b. o2 c. co2 d. h2o?

What is the difference between the electronegativity values of sodium and bromine?

Which of the following elements is the most stable element? argon, manganese, phosphorus, robidium