4.冰融化了（课件）-2024-2025学年教科版（2017）科学三年级上册

冰融化了 The ice melted 猜谜语 远看 白亮亮， 近看 玻璃样， 越冷 越坚硬， 遇热 泪汪汪。 冰 Guess riddle White and bright from a distance, If you look closely, it like the glass, The colder the harder, In the heat, it was crying. 探 究/Explore 液态的水在 ℃的时候会凝固成冰 Liquid water will freeze into ice at ℃. Can solid ice be turned back into liquid water? 那固态的冰可以重新变成液态的水吗？ 探 究/Explore 这是一些冰块，把它放置一段时间后会发生什么变化？ This is some ice. What happens when you leave it for a while? 探 究/Explore 我们可以怎样加快冰块的融化？ How can we speed up the melting of the ice? ·如果给你一台吹风机，你可以怎么做？ What would you do if you were given a hair dryer? ·如果给你一台吹风机，你可以怎么做？ What would you do if you were given a straw? ·如果给你一根吸管，你可以怎么做？ 探 究/Explore 1.讨论：你知道冰融化成水的过程中有哪些变化？ Discussion: Do you know what happens when ice melts into water? Discussion: How can we do this experiment? 2.讨论：我们可以怎么做实验？ 3.用以下实验材料，我们可以怎么做这个实验？ 冰块、烧杯、热水、酒精灯、记号笔 How can we do the experiment with the following materials? Ice cube、beaker、hot water、alcohol lamp、mark pen 实 验/Experiment 1.在烧杯中加入3-5个冰块，用笔标记冰块的高度 2.将温度计插入到烧杯中，测量烧杯中冰的温度 3.保持温度计位置不变，等待烧杯中的冰融化 4.测量烧杯中的冰融化一半时的温度 5.冰完全融化后，测量烧杯中的水的温度 Fill a beaker with 3-5 ice cubes, and mark the height of the cubes with a pen . Insert the thermometer into the beaker and measure the temperature of the ice in the beaker. Hold the thermometer in the same position and wait for the ice in the beaker to melt. Measure the temperature of the ice in the beaker when it is half melted. After the ice has melted completely, measure the temperature of the water in the beaker. 探 究/Explore ·冰融化成水的原因是什么？ ·冰在融化过程中形态发生了什么变化？ ·冰完全融化成水体积有什么变化吗？ What causes ice to melt into water? What happens to the shape of the ice as it melts? Is there any change in volume when the ice melts completely into water? ·你还观察到其它什么现象？ What else have you observed? 探 究/Explore 取两个烧杯，其中一个烧杯内放入1个冰块，另一个烧杯中放入大量冰块，哪个烧杯中的冰块会先全部融化成水呢？ Take two beakers, Place an ice cube in one beaker and a large amount of ice in the another . Which beaker will melt into water first? 总 结/Summarize ·和水蒸气一样，冰也是水的另一种形态 Like water steam, ice is another form of water ·冰融化成水需要从周围吸收热量 Melting ice into water requires the absorption of heat from its surroundings 总 结/Summarize 水在自然界有气态、液态、固态三种存在状态，水的状态变化与热量有关，水的三种状态之间是可以互相转化的。 水 冰 水蒸气 用箭头标出水、水蒸气和冰的转化关系。 Use arrows to show the relationship between water, steam and ice. 它们是同一种物质 水 ① 受热/Be heated ② 遇冷/Be colded $$