Question
A student wants to conduct an investigation that will determine a physical property of an unknown substance. Which of the following procedures would best measure a physical property of the unknown sample?
Responses
A 1. Create an acidic solution by adding 5 mL vinegar to 100 mL water
2. Place the sample into the acidic solution
3. Observe if the sample begins to fizz in the solution
4. Record your observations1. Create an acidic solution by adding 5 mL vinegar to 100 mL water 2. Place the sample into the acidic solution 3. Observe if the sample begins to fizz in the solution 4. Record your observations
B 1. Using tongs, hold the sample over a flame
2. Observe if the sample catches on fire
3. Record your observation1. Using tongs, hold the sample over a flame 2. Observe if the sample catches on fire 3. Record your observation
C 1. Place the sample in a resealable, zip-top bag
2. Firmly close the zip-top bag
3. Lightly tap the sample with a hammer
4. Observe if the sample dents, breaks, or shatters
5. Record your observations1. Place the sample in a resealable, zip-top bag 2. Firmly close the zip-top bag 3. Lightly tap the sample with a hammer 4. Observe if the sample dents, breaks, or shatters 5. Record your observations
D 1. Break the sample into a fine powder
2. Add the powder to a 500 mL beaker
3. Add 300 mL of water to the beaker and use to stirring rod to mix
4. Using a dropper, add 4 drops of universal pH indicator to the solution
5.Observe any color change in the sample
6. Record your observations
Responses
A 1. Create an acidic solution by adding 5 mL vinegar to 100 mL water
2. Place the sample into the acidic solution
3. Observe if the sample begins to fizz in the solution
4. Record your observations1. Create an acidic solution by adding 5 mL vinegar to 100 mL water 2. Place the sample into the acidic solution 3. Observe if the sample begins to fizz in the solution 4. Record your observations
B 1. Using tongs, hold the sample over a flame
2. Observe if the sample catches on fire
3. Record your observation1. Using tongs, hold the sample over a flame 2. Observe if the sample catches on fire 3. Record your observation
C 1. Place the sample in a resealable, zip-top bag
2. Firmly close the zip-top bag
3. Lightly tap the sample with a hammer
4. Observe if the sample dents, breaks, or shatters
5. Record your observations1. Place the sample in a resealable, zip-top bag 2. Firmly close the zip-top bag 3. Lightly tap the sample with a hammer 4. Observe if the sample dents, breaks, or shatters 5. Record your observations
D 1. Break the sample into a fine powder
2. Add the powder to a 500 mL beaker
3. Add 300 mL of water to the beaker and use to stirring rod to mix
4. Using a dropper, add 4 drops of universal pH indicator to the solution
5.Observe any color change in the sample
6. Record your observations
Answers
GPT-4o mini
To best determine a physical property of an unknown substance, the procedure should focus on characteristics that do not change the chemical identity of the substance. Among the provided options, the best choice would be:
**Option C:**
1. Place the sample in a resealable, zip-top bag
2. Firmly close the zip-top bag
3. Lightly tap the sample with a hammer
4. Observe if the sample dents, breaks, or shatters
5. Record your observations
This procedure directly measures a physical property related to the sample's hardness or malleability without changing its chemical structure. The other options (A, B, and D) involve chemical reactions or properties (like acidity and flammability) which are not physical properties, making Option C the most appropriate for measuring a physical property.
**Option C:**
1. Place the sample in a resealable, zip-top bag
2. Firmly close the zip-top bag
3. Lightly tap the sample with a hammer
4. Observe if the sample dents, breaks, or shatters
5. Record your observations
This procedure directly measures a physical property related to the sample's hardness or malleability without changing its chemical structure. The other options (A, B, and D) involve chemical reactions or properties (like acidity and flammability) which are not physical properties, making Option C the most appropriate for measuring a physical property.