The arrows in the chart below represent phase transitions. Which arrows represent the phase transitions in which heat energy is gained?
1, 2, and 3
2, 3, and 5
3.4. and 5
4.5 and 6

It is a mixture. simply put, a compound must be pure, that is, of only one chemical structure and composition. a mixture is made of different chemical substances (i.e. elements, molecules, compounds) that are not chemically bonded to each other, but instead physically grouped together, as in the case of gasoline (a homogeneous solution).

Answer charle's law