Which subatomic particle is the hardest to observe and why

The goal of this experiment was to answer the question "what is the effect of a gas' temperature on its volume? " you formulated the hypothesis below. hypothesis: if a fixed amount of gas is heated, then the volume will increase because the heat will cause the molecules of gas to move faster and further apart. to test this hypothesis, you changed the of the gas between 0 and 100°c (273 and 373 k) and calculated the resulting of the gas.