Solutions, Mixtures, Acids and Bases

The air we breathe contains different individual gases (mostly nitrogen and oxygen). Which of the following correctly describes the air we breathe?

• Mixture

• Liquid

• Compound

• Element

The juice we drink contains different individual solids and liquids (mostly sugars and acids). Which of the following correctly describes the juice we drink?

• Mixture

• Liquid

• Compound

• Element

When salt is dissolved in water, the resulting solution is a...

• element

• compound

• homogeneous mixture

• heterogeneous mixture

When salt, vinegar and spices are mixed in oil, the resulting solution is a...

• element

• compound

• homogeneous mixture

• heterogeneous mixture

Coffee is a solution made by placing coffee grounds into a paper filter and then pouring very hot water over the coffee grounds. Which statement below correctly identifies the solute and the solvent of this solution?

• The coffee grounds are the solvent and water is the solute

• The coffee grounds are the solute and the water is the solvent

• The coffee grounds are the solvent and the paper filter is the solute

• The coffee grounds are the solute and the paper filter is the solvent

Based on this table, which of the following statements is correct?

• Orange juice is more acidic than black coffee

• Stomach acid is more basic than orange juice

• Bleach is more acidic than household ammonia

• Toothpaste is more basic than household ammonia

Margaret tests four solutions to determine whether they are acidic, basic, or neutral. She records her results in a lab notebook.

Which of the following statements from Margaret's lab notebook indicates she is testing an acid?

• I put on protective gloves and touched the solution. It felt slippery as if I were touching wet soap

• I added some drops of a bromothymol blue indicator solution, and the color indicated a pH of about 7.0 on the scale

• I placed a drop of oil into the solution in the beaker. After two minutes, I noticed that the solution had dissolved the oil

• I dipped a universal indicator strip into the beaker of the solution. The strip turned orange, matching a pH range of 3.0 to 4.0 on the color scale

Which of the following statements best describes why salad dressing is classified as a heterogeneous mixture?

• It is uniform in composition and the parts that make up the mixture can be separated from one another through physical means

• It is not uniform in composition and the parts that make up the mixture can be separated from one another through physical means

• It is uniform in composition and the parts that make up the mixture cannot be separated from one another through physical means

• It is not uniform in composition and the parts that make up the mixture can be separated from one another through chemical means

Which of the following statements best describes why milk is classified as a homogeneous mixture?

• It is uniform in composition and the parts that make up the mixture can be separated from one another through physical means

• It is not uniform in composition and the parts that make up the mixture can be separated from one another through physical means

• It is uniform in composition and the parts that make up the mixture cannot be separated from one another through physical means

• It is not uniform in composition and the parts that make up the mixture can be separated from one another through chemical means

H₂O is...

• a compound

• an element

• a heterogenous mixture

• a homogeneous mixture