A balloon is filled with 3.8 L of helium gas at 1 atmosphere. The balloon is released and goes up to an altitude (top of a mountain), where the pressure is decreased to 0.25 atmospheres. The new volume is:

On a distance vs time graph the line of an object at rest is a

Consider hydrogen in an excited state n = 5n=5 that emits photons to reach the ground state. there are various possible transitions other than straight to the ground state that can occur; for example, it can drop to the n = 3n=3 state followed by the n = 3n=3 to the ground state transition. which of the possible transitions will result in the emission of a photon in the visible region?

Calculate the percent composition by mass of each element in al(oh)3. use at least three significant figures.