Eliot is given a sample of unknown liquid to test in the
laboratory. Eliot thinks that the liquid is water, but he isn't
sure. Which of the following would be most helpful for Eliot
to test in order to determine whether or not the liquid is
water?
There are a few tests Eliot can conduct to determine whether the unknown liquid is water or not. Here are some options:
1. Density: Eliot can measure the density of the liquid and compare it to the known density of water. If the density of the unknown liquid matches the density of water (1 g/cm³), then it is likely water.
2. Boiling point: Water has a boiling point of 100 degrees Celsius (212 degrees Fahrenheit) at sea level. Eliot can heat the liquid and observe at what temperature it starts boiling. If the boiling point matches 100 degrees Celsius, then it is likely water.
3. Freezing point: Water freezes at 0 degrees Celsius (32 degrees Fahrenheit). Eliot can lower the temperature of the liquid and observe when it starts to freeze. If it freezes at 0 degrees Celsius, then it is likely water.
4. pH level: Water has a neutral pH of 7, while other substances might have different pH levels. Eliot can use pH paper or a pH meter to test the acidity or alkalinity of the liquid. If the pH is around 7, then it is likely water.
5. Conductivity: Water is a good conductor of electricity due to its dissolved ions. Eliot can use a conductivity tester to check if the liquid can conduct electricity. If it conducts electricity well, then it is likely water.
Using one or a combination of these tests, Eliot can determine whether the unknown liquid is water or not.
To determine whether the unknown liquid is water or not, Eliot can perform a few tests. The following steps can help in the process:
1. Measure the boiling point: Water has a boiling point of 100 degrees Celsius at sea level. If the liquid reaches this temperature and undergoes a phase change from liquid to gas, it suggests that it might be water.
2. Conduct a freezing point test: Water freezes at 0 degrees Celsius. If the liquid undergoes a phase change from liquid to solid at this temperature, it indicates that it is likely water.
3. Perform a density test: Water has a known density of approximately 1 g/cm^3 at room temperature. Comparing the density of the unknown liquid to the density of water can provide clues about its identity.
4. Test for electrical conductivity: Water is a good conductor of electricity due to the presence of ions. Using a conductivity tester, if the liquid allows electric current to pass through, it suggests that it could be water.
5. Perform a pH test: Water has a neutral pH of 7. Using pH test strips or a pH meter, if the unknown liquid has a pH of 7, it may indicate that it is water.
By performing these tests, Eliot will be able to gather enough evidence to determine whether or not the unknown liquid is water.