In a physical science class, four students are experimenting with distinct techniques for dissolving laundry soap in water. Each student mixes 20 grams of soap with 1000 mL of water. The table illustrates the varied methods employed by each student.

Question

Student: Darien | Form of soap: Solid cube | Water temperature: 50°C | Method of combination: No stirring
Student: Heather | Form of soap: Powder | Water temperature: 105°C | Method of combination: Vigorous stirring
Student: Abdullah | Form of soap: Solid cube | Water temperature: 50°C | Method of combination: Gentle stirring
Student: Larissa | Form of soap: Powder | Water temperature: 75°C | Method of combination: Gentle stirring
Among the options provided, which sequence most likely represents the order in which the students' laundry soap completed dissolution, ranging from the first to finish to the last?

Answer 1

To determine the order in which the students' laundry soap completed dissolution, we need to consider several factors: the form of soap (solid cube vs. powder), water temperature, and the stirring method.

1. Form of Soap: Powdered soap generally dissolves more quickly than solid cubes due to its increased surface area.

2. Water Temperature: Higher temperatures typically increase the solubility of substances in water. Among the students, Heather uses the hottest water at 105°C, followed by Larissa at 75°C, and both Darien and Abdullah at 50°C.

3. Stirring Method: Vigorous stirring is more effective at promoting dissolution than gentle stirring or no stirring at all.

Considering all these factors, the students' dissolution order would likely be:

1. Heather: Powdered soap at 105°C with vigorous stirring – This will likely lead to the fastest dissolution.
2. Larissa: Powdered soap at 75°C with gentle stirring – The powdered form should dissolve quickly, although not as fast as Heather's method.
3. Abdullah: Solid cube at 50°C with gentle stirring – Gentle stirring limits the dissolution rate, and the solid cube form makes it slower than powdered soap.
4. Darien: Solid cube at 50°C with no stirring – Without stirring, the dissolution will be the slowest among the methods used.

So, the correct order from first to last in dissolving the laundry soap is: Heather, Larissa, Abdullah, Darien.