Many cities have to deal with icy roads during the winter. To fix the problem, city workers pour salt onto the roads. Which rule about the physical world are they using? A. Sand can also be used to treat icy roads. B. Damage to cars resulting from salted roads has cost people billions of dollars. C. Many cities use salt to deice roads. D. Salt helps ice melt at colder temperatures.

When city workers pour salt onto icy roads, they are leveraging the fascinating science of freezing point depression. Salt lowers the freezing point of water, allowing the ice to melt even at temperatures below 0°C (32°F). This is why roads are treated with salt to prevent slips and accidents! In real-world applications, this method of de-icing not only helps keep roads safer for drivers during the winter months but also comes with its own set of challenges. Too much salt can lead to environmental issues like soil degradation and harm to plant life, prompting cities to explore more sustainable alternatives, such as beet juice or magnesium chloride!