What if things in the natural world were not predictable? What if quartz was hard in one place and as soft as a marshmallow in another? What if oil was slippery one moment, but sticky the next? Thankfully, God made laws to govern nature. We can learn how things like salt behave. Then we can make use of what He created. You can achieve the same results we did when you do these experiments, all because of God’s orderly creation.
Salt makes water dense.
Dense means “packed tightly together.” Salt water packs more molecules into the same space than fresh water does. Salt water can be more dense than an egg.
• Fill a large drinking glass with cold tap water. Place a raw egg in the glass. The egg sinks to the bottom of fresh tap water.
• Stir six teaspoons of salt into the water. The egg floats in the denser salt water.
• Leave the egg in the first glass of salt water. Fill another glass with fresh, cold tap water. Add six drops of food coloring to that glass.
• Lay a strip of paper towel over the rim of the glass of salt water. Loop it down so that it rests on the surface of the salt water.
• Pour the colored fresh water slowly and gently down the side of the paper towel so as not to stir up the salt water. Less dense, fresh water stays above heavier salt water. How long does it take before it mixes in?
Salt helps water conduct electricity.
• Strip both ends of two pieces of wire. Speaker wire works well.
Tape the end of one wire to a terminal of a 9-volt battery. Tape an end of the other wire to the other terminal.
• Dip the bare ends of the wires in warm, plain, fresh tap water. Nothing happens.
• Stir six teaspoons of table salt into the water. Dip the wires. Bubbles form, showing that electricity is flowing through the salt water. Salt is one of the electrolytes your body needs. Electrolytes carry tiny electric signals to work your nerves, heart, brain, and more.
Salt lowers the freezing point of water.
• Fill a bowl with ice cold, fresh tap water. Place an ice cube into the water. Dangle string so it rests on top of the floating ice cube. Sprinkle a little salt onto the string where it rests on the ice cube. Wait about a minute. You can lift the cube with the string. Salt melts a little of the ice cube. The little bit of salt water lowers the temperature of the top of the ice, which refreezes around the string.
