Which of the following is a chemical reaction?

• Calcium chloride dissolves in water.

• A balloon pops.

• Soft-drink powder mixes with water and the water turns red.

• A nail is dropped in the yard and rusts.

Tags

NGSS.MS-PS1-2

A student mixed two saltwater solutions and weighed 50 mL of each. Solution 1 had a mass of 64 g. Solution 2 had a mass of 48 g. Which is true?

• Solution 1 is less dense and less concentrated than Solution 2.

• Solution 1 is less dense and more concentrated than Solution 2.

• Solution 1 is more dense and more concentrated than Solution 2.

• Solution 1 is more dense and less concentrated than Solution 2.

Tags

NGSS.MS-PS1-2

A solution has 20 g salt and 100 mL water. What would make the solution half as concentrated?

• Add 10 g salt.

• Add 50 mL water.

• Add 20 g salt.

• Add 100 mL water.

Solution A has 10 g solid. Solution B has 12 g solid. Both have equal amounts of water. Which is true?

• A is less concentrated and less dense.

• A is less concentrated and more dense.

• B is less concentrated and less dense.

• A is more concentrated and less dense.

Which is a substance made up of only one kind of atom?

• element

• mixture

• solution

• compound

Two spoons of solid are mixed in 50 mL water and the solid dissolves. The mass of one spoon of solid is 4 g. What is the mass of the solution?

• 8 g

• 58 g

• 52 g

• 54 g

Tags

NGSS.MS-PS1-5

Two spoons of solid are mixed in 50 mL water and the solid dissolves. The mass of one spoon of solid is 4 g. After the water evaporates, what will be the mass of the remaining solid?

• 4 g

• 52 g

• 8 g

• 58 g

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

A student dissolves 15 g of solid in 200 mL of water. Which is true?

• The solution's mass is less than the mass of the water.

• The solution's mass is greater than the mass of the water.

• The solution's mass is the same as the mass of the water.

• You cannot tell from the information given.

Tags

NGSS.MS-PS1-5

Which of these makes both a mixture and a solution?

• salt and pepper

• calcium chloride and salt

• citric acid and water

• water and sand

Why do we heat water when adding sugar to make candy?

• So the solution will condense more quickly

• So the solution will evaporate

• So the solution will become saturated right away

• So the solution is highly concentrated

Tags

NGSS.MS-PS1-4

NGSS.MS-PS3-4