Unit 2, Solubility/Solutions ( 5.P.8.2)

1. In an experiment, two students timed how long salt took to dissolve in water under the four conditions shown below. Condition 1: No stirring and no heat Condition 2: Stirring and no heat Condition 3: No stirring with heat Condition 4: Stirring and heat The students carefully recorded the time it took for the salt to dissolve under each set of conditions. However, they forgot to label which condition went with each set of times. The table shows the data from the three trials. Which set of data most likely shows the beaker in Condition 4, with stirring and heat?

• Beaker 1

• Beaker 2

• Beaker 3

• Beaker 4

Tags

NGSS.MS-PS1-2

Family members on a camping trip decide to make hot cocoa after dinner. They add instant cocoa mix to hot water. What can they do to make the cocoa mix dissolve faster?

• stir the hot cocoa

• halve the amount of water

• double the amount of cocoa mix added

• add the cocoa mix after the water cools

Maria likes iced tea and her mom likes hot tea. Maria poured the same amount of hot tea into a glass with ice as her mom poured into a cup. Then they stirred the same amount of sugar into each of their teas. After they both finished their tea, Maria noticed there was still sugar at the bottom of her glass, while her mom’s cup did not have any sugar left. What was the most likely reason that sugar was left at the bottom of the iced tea but NOT at the bottom of the hot tea?

• Maria’s drink was stirred more.

• Maria’s glass had less tea in it than her Mom’s cup had.

• Maria’s drink was in a glass and her Mom’s was in a cup.

• Maria’s tea was at a lower temperature than her Mom's tea

Tags

NGSS.MS-PS1-4

NGSS.MS-PS3-4

Ken needs to design an experiment that shows how the surface area of sugar affects the rate at which the sugar will dissolve in water. Which of the following statements describes the best way to show the relationship between particle size and rate of dissolving?

• Time how fast loose sugar dissolves in water at room temperature and how fast loose sugar dissolves in hot water.

• Time how fast a cube of sugar dissolves in water at room temperature and how fast loose sugar dissolves in hot water

• Time how fast a cube of sugar dissolves in water at room temperature and how fast a cube of sugar dissolves in hot water.

• Time how fast a cube of sugar dissolves in water at room temperature and how fast loose sugar dissolves in water at room temperature.

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-4

.A student is making a list of items that will not dissolve in water. Which of the following substances can be added to this list?

• salt

• soap

• sugar

• oil