Engineering Commons^™

Activity 3: Rooting For You, Karen Ye

Theme 4: Please Pass the Salt

Snow and ice removal are needed in winter for safe roads. Salt is very effective along with other chemicals, but these may cause harm to plants, wildlife, and humans. Salt seeps into groundwater and may create problems with water resources. High levels of salt affects the amount of oxygen in water, organism growth, reproduction, and food sources. Whether the chemicals cause harm to an organism depends on the amount of chemicals and how long the organism is exposed to them. Salt can also reduce soil minerals and absorb water that plants need. Other impacts on plants include leaf damage, stunted …

Activity 2: A Little Bit Salty, Karen Ye

Theme 4: Please Pass the Salt

Density is defined as the amount of mass that takes up a certain amount of volume. Adding salt or sugar to water increases its density since there are more particles (mass) packed into a similar amount of space (volume). Cooling water can also increase its density since the particles move more slowly at lower temperatures and will be more packed together. When two substances with different densities are combined, the one with a lower density will float whereas the one with a higher density will sink. The greater the difference in density, the more distinct the layers and the harder …

Activity 1: Cooler Than Me, Karen Ye

Theme 4: Please Pass the Salt

All matter is made up of atoms and molecules. Even though we can’t see them with our bare eyes, these tiny particles are constantly moving. The temperature of a substance is a measure of its average kinetic energy (the energy it has due to the motion of the particles). As the temperature increases, particles gain more energy, move more quickly and spread further apart.

No matter where one lives in Illinois, you are impacted by winter weather. Deicing and snow removal account for a large portion of state and local highway budgets. Salt is commonly used for melting snow and …

Activity 4: Green Winterization, Karen Ye

Theme 4: Please Pass the Salt

Materials other than salt are also used to mitigate the dangers of ice and increase traction. Additional materials used include sand, calcium chloride, and a mixture of salt brine and beet juice. The use of each method involves trade-offs.