*will pick brainliest*
how do i work this out?
avogadro's number
a gas cylinder contains exactly 15 moles of oxygen gas (o2). how many molecules of oxygen are in the cylinder?

Use the table to identify the phase and phase changes of the elements under the given conditions. write the name of the substance, phase, or phase change. when the temperature in a room increases from 25°c to 33°c, changes from a solid to a liquid. in a lab, methane and nitrogen are cooled from -170°c to -200°c. the methane freezes and the nitrogen . when gold is heated to 2,856°c it changes from a liquid to a .

An aqueous solution of hydroiodic acid is standardized by titration with a 0.186 m solution of calcium hydroxide. if 26.5 ml of base are required to neutralize 20.3 ml of the acid, what is the molarity of the hydroiodic acid solution? m hydroiodic acid

If a sample of radioactive isotopes takes 600 minutes to decay from 400 grams to 50 grams, what is the half-life of the isotope?