SCIENCE - WRITTEN WORK 2 Multiple Choice: Read each question carefutly and choose the letter of the best answer. Write your answer in your answer sheet. 1. What happens when chocolate melts? A. The particles of chocolate lose their orderly arrangement to form gas. B. The particles of chocolate lose their ordeny arrangement to form liquid. C. The particies of chocolate keep their orderly arrangement to form liquid. D. None of these. 2. What happens when a chocolate drink freezes? A. It absorbs heat. and the particles lose kinetic energy. B. It releases heat, and the particles lose kinetic energy. C. It absorbs heat. and the particles lose potential energy. D. It releases heat. and the particles lose potential energy. 3. What happens when alcohol evaporates? A. It absorbs energy causing particles to vibrate faster. B. It absorbs energy causing particles to vibrate slower. C. It releases energy causing particles to vibrate faster. D. It releases energy causing particles to vibrate slower. 4. Which is TRUE about deposition? A. It is responsible in cloud formation B. It is responsible in snow formation C. It is the exact apposite of evaporation D. It occurs substance changes directly from solid to gas 5. Which is NOT TRUE about evaporation? A. It occurs when matter absorbs energy B. It occurs when gaseous substance turns to liquid 0. It occurs when a substance turns from liquid to gas D. It occurs when the kinetic energy of the particles increases WEEK 2 MODULE 2: Phase Changes of Matter Matter commonly exists on earth in three forms: solid, liquid. or gas- which are called as three states of matter. The main difference of the three is based on how the molecules move. Solid molecules are tightly packed and cannot move much, liquid molecules have more space and can move freely, while gas molecules are farther and move very fast. In this lesson, you will learn more about the physical changes matter undergo. What Are the Phase Changes of Matter? Matter undergoes changes in physical state known as phase changes. Phase changes occur by either absorption or release of energy usually in the form of heat. Melting happens when solid turns to liquid. When solid is heated. it absorbs energy enough to overcome the force that holds the particles *M v? together. The attraction between particles . M # becomes less allowing them to move freely. When '. this happens, the melting point of the solid is OLID reached and the solid melts. Melting point is the temperature at which solid tums into a liquid mum Fig. 2.1 This illustrate the particles of a solid matter when it tums to liquid. The arrows represent the motion of the particles. (Source: shutterstockcom) If more heat is added, liquid particles move rapidly and farther apart. At this point, boiling point is w? 9\" reached. Boiling point is the temperature at which LIQUID '9' GAS vapor pressure becomes high that causes '0'. \\. JV bubbles to form inside the body of the liquid and evaporation happens. m is the change from liquid to gas_ As \"quid absorbs energy when Flg. 2.2 This illustrate the particles 0* a liquid substance when it heated the closer particles of liquid become turnstogas. The arrows represent the motion ofthe particles. separated. There will be less attraction between (Source: shutterstockcom) particles which allows them to move freely. The reverse process can also happen. A gas can 0". be cooled to become liquid. This process is called /. N f . . NF condensation. Condensation happens when a \\. K '. _" '0';- gas turns into a liquid. When a gas loses heat, the particles become closer and roll over as it turns into liquid. GAS LIQUID Fig. 2.3 This illustrate the particles of a gaseous substance when it turns to liquid. The arrows represent the motion of the particles. (Source: sh utterstockcom) Further cooling of the liquid causes freezing or solidication. This process allows the particles to get closer and have rigid position. The particles can no longer move freely instead, they will just vibrate. The temperature wherein a liquid solidifies is called freezing point. .3310 * +++ ++.->