<p> People Search for Review</p><p>1. What is the difference between a mixture and a compound? Give an example of each. </p><p>2. Describe a proton. Why are electrons ignored when finding the mass of an atom? Where are each of the subatomic particles found in an atom?</p><p>3. What determines if an atom is an ion or not? Draw a Bohr model of an ion of helium.</p><p>4. What is an isotope? What makes an isotope of one element different from a different isotope of the same element?</p><p>5. Describe the arrangement of atoms in a solid, liquid and a gas of a substance. Rank the states of matter in order of highest energy to lowest energy. 6. Describe what happens to the molecules of air in a hot air balloon in terms of a) pressure; b) density; c) motion; and d) number of collisions when the balloonist heats the air.</p><p>7. What happens to the energy of particles as they are heated? What happens to temperature of the particles?</p><p>8. Sketch a phase diagram for water. Label the graph where the water is a) liquid; b) solid; c) gas; d) melting; e) boiling.</p><p>Sign for 3 problems which you feel confident in completing.</p><p>1. ______5. ______</p><p>2. ______6. ______</p><p>3. ______7. ______</p><p>4. ______8. ______</p>