3. True or False. A compound is formed when two or more elements are
False
True

Calculate the number of kilojoules to warm 125 g of iron from 23.5°c to 78.0°c.

What happens to the average kinetic energy of a gas when the particles of the gas collide against each other at a constant temperature and volume? explain your answer.

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?