Someone please help
5x+15 7x-11

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.

Which substance has non polar covalent bonds

Water undergoes a large change in density at 0 ∘ c as it freezes to form ice. calculate the percent change in density that occurs when liquid water freezes to ice at 0 ∘ c given that