# Salt Level Demonstration

Salt Level Demonstration teacher's guide

#### TEACHER'S GUIDE

What appears to be very little salt can cause big environmental changes like changing freshwater to saltwater.

##### Materials
• Water
• Salt
• Digital scale, if available; or measuring cup and spoons
##### Demonstration

Key Idea: What appears to be very little salt can cause big environmental changes like changing freshwater to saltwater.

Use a 1000 ml graduated cylinder and a digital gram scale if available to measure out:

1. 1 mg table salt and 1000 ml of water = Salt levels of 1mg/L (freshwater)
2. 250 mg table salt and 1000 ml of water = Salt levels of 250 mg/L (EPA drinking water guidelines; freshwater)
3. 1 gram table salt and 1000 ml of water = Salt levels of 1000 mg/L (considered slightly salty; brackish water)
4. 3 grams table salt and 1000 ml of water = Salt levels of 3000 mg/L (NY/NJ Harbor Estuary water, considered moderately salty; estuary water that changes with the tides)
5. 10 grams table salt and 1000 ml of water = Salt levels of 10,000 mg/L (NY/NJ Harbor Estuary water considered very salty)
6. 35 grams table salt and 1000 ml of water = Salt Levels of 35,000 mg/L (Very salty; open ocean water)
##### Teacher Tip

Use teaspoons and a measuring cup to measure out the same quantities, so that students can taste the differences in salt:

1. A. 1mg/L ~ 0 tsp. of salt in 4 ¼ cups of water
2. B. 250 mg/L ~ 1/19 tsp. salt in 4 ¼ measuring cups of water
3. C. 1000 mg/L ~ 1/4 tsp. salt in 4 ¼measuring cups of water
4. D. 3000 mg/L ~ 5/8 tsp. salt in 4 ¼ measuring cups of water
5. E. 10,000 mg/L ~ 2 and 1/8 tsp. salt in 4 ¼ measuring cups of water
6. F. 35,0000 mg/L ~ 7 and 1/3 tsp. salt in 4 ¼ measuring cups of water