科学素养与生活应用·英语30篇（4）

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为何盐能降低结冰路面上水的凝固点

Salt dissolves in thin layers of water that naturally coat icy surfaces at subzero temperatures.
The dissolved sodium and chloride ions disrupt hydrogen bonding between water molecules.
This interference prevents ice crystals from forming or growing easily at typical winter temperatures.
As a result, the mixture freezes only below −9°C instead of 0°C under normal conditions.
Road crews apply salt strategically because its effectiveness declines below −12°C.
Calcium chloride works better in extreme cold since it releases heat when dissolving.
However, overuse damages concrete, corrodes vehicles, and harms nearby vegetation and soil.
Scientists are testing beet juice and cheese brine as eco-friendly alternatives with similar freezing-point depression.
The principle also explains why seawater stays liquid longer than freshwater in polar regions.
Freezing-point depression is a colligative property—it depends only on particle concentration, not identity.

听 → 读 → 学表达 → 懂 → 今天会说这一句 → 跟读录音 → 自己说一句。

Road crews apply salt strategically because its effectiveness declines below −12°C. 道路养护人员会策略性地撒盐，因为其效果在−12°C以下会显著下降。
The dissolved sodium and chloride ions disrupt hydrogen bonding between water molecules. 溶解后的钠离子和氯离子会干扰水分子间的氢键。
However, overuse damages concrete, corrodes vehicles, and harms nearby vegetation and soil. 但过量使用会损坏混凝土、腐蚀车辆，并危害周边植被和土壤。

这篇中文题目最接近哪一句？为何盐能降低结冰路面上水的凝固点一次学校运动会的通知一份超市购物清单

课文第一句的意思更接近？盐能溶解在冰表面自然形成的薄层水中，即使在零下温度也是如此。今天学校放假了。请把窗户打开。

这一课主要在讲什么？（看英文标题） Why Salt Lowers the Freezing Point of Water on Icy Roads How to cook noodles A maths worksheet

Road crews apply salt strategically because its effectiveness declines below −12°C.

Road crews apply salt strategically because its effectiveness declines below −12°C.

第一版：录下来、回听、再听标准音。系统打分以后再加。

用今天的表达，自己说一句。

例子：Road crews apply salt strategically because its effectiveness declines below −12°C.