Question

This question has two parts.

Part A

In an experiment, students were given the task of dissolving NaCl in water to create aqueous solutions. Based on each student's experiment setup, which student completed the task fastest?


Student 1 dissolved whole NaCl tablets in 20°C water.
Student 2 dissolved crushed NaCl tablets in 20°C water.
Student 3 dissolved crushed NaCl tablets in 30°C water.
Student 4 dissolved whole NaCl tablets in 10°C water and stirred the mixture.
Select {responseValue}
Student 1

Select {responseValue}
Student 2

Select {responseValue}
Student 3

Select {responseValue}
Student 4

Part B

Which statement best supports the answer to Part A?

Select {responseValue}
The tablets had the greatest surface area.

Select {responseValue}
The tablets had the least surface area.

Select {responseValue}
The tablets had the greatest surface area and greatest temperature.

Select {responseValue}
The tablets had the least surface area and lowest temperature

...

Answer 1

**Part A**
The fastest dissolution of NaCl would likely occur under conditions that maximize surface area and temperature.

Among the students:
- Student 1: whole NaCl tablets in 20°C water.
- Student 2: crushed NaCl tablets in 20°C water.
- Student 3: crushed NaCl tablets in 30°C water.
- Student 4: whole NaCl tablets in 10°C water and stirred.

Student 3 likely completed the task fastest because they used crushed NaCl (which has a greater surface area than whole tablets) in warmer water (30°C) which speeds up the dissolution process.

**Response:**
Select **Student 3**

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**Part B**
To support the answer that Student 3 dissolved the NaCl fastest, the best statement would relate to both surface area and temperature, as both factors contribute positively to the rate of dissolution.

**Response:**
Select **The tablets had the greatest surface area and greatest temperature.**