investigations were carried out in a science lab to explore the topic of chemical and physical…

investigations were carried out in a science lab to explore the topic of chemical and physical changes.\ninvestigation a\nstep 1. add 5 tsp. salt to 100 ml warm water and stir until most or all of the salt is no longer visible.\nstep 2. heat the salt solution on a burner until only a white solid remains.\ninvestigation b\nstep 1. mix 10 tsp. white sugar into 100 ml water and stir until most or all of the sugar is no longer visible.\nstep 2. heat the sugar solution on a burner until the solution thickens and turns brown.\nin which step(s) did a chemical change most likely occur?\ninvestigation a, step 1 and investigation b, step 1\ninvestigation a, step 2 and investigation b, step 2\ninvestigation a, step 2 only\ninvestigation b, step 2 only

investigations were carried out in a science lab to explore the topic of chemical and physical changes.\ninvestigation a\nstep 1. add 5 tsp. salt to 100 ml warm water and stir until most or all of the salt is no longer visible.\nstep 2. heat the salt solution on a burner until only a white solid remains.\ninvestigation b\nstep 1. mix 10 tsp. white sugar into 100 ml water and stir until most or all of the sugar is no longer visible.\nstep 2. heat the sugar solution on a burner until the solution thickens and turns brown.\nin which step(s) did a chemical change most likely occur?\ninvestigation a, step 1 and investigation b, step 1\ninvestigation a, step 2 and investigation b, step 2\ninvestigation a, step 2 only\ninvestigation b, step 2 only

Answer

Answer:

Investigation A, Step 2 and Investigation B, Step 2

Explanation:

Step1: Define chemical change

A chemical change results in new substances.

Step2: Analyze Investigation A Step 1

Dissolving salt in water is a physical change as no new substance forms.

Step3: Analyze Investigation A Step 2

Heating salt solution to get white solid is evaporation (physical). But if impurities react, could be chemical.

Step4: Analyze Investigation B Step 1

Dissolving sugar in water is physical, no new substance.

Step5: Analyze Investigation B Step 2

Heating sugar solution to brown - thick substance is caramelization, a chemical change forming new substances.