Which of the following is a physical change? Which is a chemical change?
1. Heating wax until it melts Physical Chemical Physical and Chemical( Physical, Chemical, Physical and Chemical )
2. Crush some salt crystals into a powder Physical Chemical Physical and Chemical( Physical, Chemical, Physical and Chemical )
3. Boiling water until it evaporates, then condensing the
steam. Physical Chemical Physical and chemical( Physical, Chemical, Physical and chemical )
4. Boiling an egg in boiling water for two minutes, then
cooling the water. Physical Chemical physical and chemical( Physical, Chemical, physical and chemical )
5. Heating a piece of paper until it turns black, then cooling
it. Physical chemical physical and chemical( Physical, chemical, physical and chemical )
6. Heating a mixture of hydrogen and oxygen until it
“pops”, and then cooling the gases to a liquid. Physical Chemical physical and chemical( Physical, Chemical, physical and chemical )
7. Dissolving salt into water to make a solution Physical Chemical physical and chemical( Physical, Chemical, physical and chemical )
8. Cooking a steak until it is well done Physical Chemical physical and chemical( Physical, Chemical, physical and chemical )
9. Burning magnesium ribbon in air Physical chemical physical and chemical( Physical, chemical, physical and chemical )

Which of the following is a physical change? Which is a chemical change?

burning a piece of wood Chemical change Physical change( Chemical change, Physical change )
dissolving copper sulfate in water to obtain a blue solution Physical change Chemical change( Physical change, Chemical change )

State if the following processes is endothermic or exothermic?
1. Heating water from 20°C to 80°C. Endothermic Exothermic( Endothermic, Exothermic )
2. Heating water from 20°C through to boiling continuously at 100°C. Endothermic Exothermic( Endothermic, Exothermic )
3. The burning of a magnesium ribbon in air Endothermic Exothermic( Endothermic, Exothermic )
4. The reaction that takes place when a spark is introduced to a mixture of H2 and O2 gas. Endothermic Exothermic( Endothermic, Exothermic )
5. Any reaction or process that consumes heat energy. Endothermic Exothermic( Endothermic, Exothermic )
6. The process of cooling liquid paradichlorobenzene until it solidifies. Endothermic Exothermic( Endothermic, Exothermic )
7. The decomposition of water into H2 and O2 gas. Endothermic Exothermic( Endothermic, Exothermic )
8. Any reaction or process that releases heat energy Endothermic Exothermic( Endothermic, Exothermic )
9. Condensation of steam Endothermic Exothermic( Endothermic, Exothermic )
10. Sublimation of iodine. Endothermic Exothermic( Endothermic, Exothermic )
11. Vaporization of ethanol Endothermic Exothermic( Endothermic, Exothermic )