Level 1 · Reading series
Lesson 29 · Salt on Ice
Audio track 29
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We put two ice cubes on a plate. We spread salt on one cube. Soon, that cube begins to melt faster.
Pure water usually freezes at zero degrees Celsius. Salt makes its freezing point lower. The salty water can stay liquid at a temperature below zero.
People sometimes put salt on an icy road, but it is less useful in very cold weather. Too much salt can also harm plants and metal.
Sentence practice
Play any sentence in Dicvo’s Jenny English voice. Before playing all, choose how many times each sentence plays. A practice pause about as long as the sentence follows each play, including before the next sentence. The complete reading remains above.
Choose a sentence to begin.
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We put two ice cubes on a plate.
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We spread salt on one cube.
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Soon, that cube begins to melt faster.
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Pure water usually freezes at zero degrees Celsius.
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Salt makes its freezing point lower.
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The salty water can stay liquid at a temperature below zero.
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People sometimes put salt on an icy road, but it is less useful in very cold weather.
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Too much salt can also harm plants and metal.
Check your understanding
After reading, state the main idea in one sentence and find a line that supports it.
Chinese translation
我们把两块冰放在盘子上，往其中一块上撒盐。不一会儿，撒了盐的冰块开始融化，而且融化得更快。
纯水通常在摄氏零度结冰。盐会降低水的凝固点，所以盐水在低于零度时仍可能保持液态。
人们有时会在结冰的路面撒盐，但天气极冷时，这种做法的效果会变差。盐用得太多，还可能伤害植物和金属。
Key words and expressions
Key terms have Chinese explanations. Hover over dotted words in the English passage for word help and pronunciation when available.
- spread
- 撒开；铺开。
- salt
- 盐。
- melt
- 融化；使……融化。
- freezing point
- 凝固点；液体变成固体的温度。
- lower
- 降低；更低的。本文是动词。
- below
- 在……以下；低于……。
- icy
- 结冰的；被冰覆盖的。
- road
- 道路。
- less useful
- 不太有用；less + 形容词构成比较表达。
- harm
- 损害；伤害。
Background notes (Chinese)
盐溶于水后，水结冰所需的温度会降低，因此撒盐可用于冬季道路防冻。不过，气温过低时效果减弱；盐分也可能影响车体、植物和水环境，所以用量与方法都需要考虑。
资料来源：U.S. Geological Survey 关于道路撒盐与水质的资料。