Does not have a definite shape but has a definite volume

Which is true of chemicals? a. things containing chemicals always cost a lot of money. b. chemicals are never dangerous. c. chemicals are in many substances in a home. d. chemicals are rarely found on earth.

At a temperature of 393 k, the temperature of a sample of nitrogen is 1.07 atm what will the pressure be at a temperature of 478 k

What is the number of moles of chemical units represented by 9.03x10^24? and how do i show work? (dumb it down )