Why does sound travel at different speeds through different materials

Because if there are more space in the material the sound will travel faster

but if there is less space it will travel slower

hurricanes form when warm, moist air from the ocean surface quickly rises into the atmosphere and forms storm clouds and rain. when the clouds are formed, heat is released which warms the cool air in the upper regions of the atmosphere so that the cycle can continue. which two phases of the water cycle are repeated in this process?