Helium gas is contained in a tank with a pressure of 14.7 MPa. If the temperature inside the tank is 22.6 °C and the volume of the tank is 12.7 L, determine the mass,
in grams, of the helium in the tank.

Used the balanced equation 2h2+ o2 - -> 2h2o. if you have 7.2 grams of o2 , how many grams of h2o can you produce ?

Ageologist determines that a sample of a mineral can't be scratched by a steel nail but can be scratched by a masonry drill bit. based on this information, the sample mineral has to be softer than a. orthoclase. b. fluorite. c. apatite. d. corundum.

Draw the lewis dot structure for each of the following polyatomic ions