PLEASE HELP Q1: Give the letter of a substance that is a solid at 20 °C
Q2: Give the letter of a substance that is a liquid at 50 °C

Joseph has hypothesized that sound travels in waves. if he were following the scientific method, what should he do next? a. ask a question. b. test the hypothesis. c. study the results. d. tell other scientists about his hypothesis.

What is the volume occupied by 10.0 dm3 of gas at standard pressure after it has been compressedat constant temputure to 500.0 kpa?

8.98 dm3 of hydrogen gas is collected at 38.8 °c. find the volume the gas will occupy at -39.9 °c if the pressure remains constant.