A laboratory bottle of helium gas occupies a volume of 2.0 L at 760 mm Hg. Calculate the new pressure if the volume falls to 1.8 L.

As air becomes more dense, (select all that apply) o. air weighs less o. gas molecules are closer together o. air is colder o. air weighs more o. gas molecules are further apart o. air is hotter

12. calculate the hydroxide ion concentration of a solution with ph = 3.25. show all calculations leading to an answer

Two metal blocks that have slightly different temperatures are placed next to one another. after five minutes, they both have lower but equal temperatures. according to the law of conservation of energy, what  most likelyhappened? energy was created inside the blocks.energy was destroyed inside the blocks.energy was absorbed into the blocks from outside the system.energy was transferred from the warmer block to the cooler block.