CBA 2 (Acids/Bases, Pure vs Mixtures, LOCM, Properties of Water

Which of the diagrams below are homogeneous mixtures? Pick all that apply.

• 1

• 3

• 6

• 5

• 4

Tags

NGSS.MS-PS1-2

What do acids and bases have in common? Choose two correct answers.

• A pH of 7 indicates the liquid is both an acid and a base.

• Acids and bases can both be corrosive.

• Acids and bases are both toxic.

• Acids and bases both turn red litmus paper blue.

• Acids and bases react with each other to form a neutral solution.

Photosynthesis is the process by which green plants use carbon dioxide and water to make sugars. The chemical equation for photosynthesis is shown. 6CO₂ + 6H₂O + sunlight → C₆H₁₂O₆ + 6O₂ How many atoms are involved in the reaction?

• 26

• 30

• 36

• 72

Tags

NGSS.MS-PS1-5

NGSS.MS-LS1-6

Is this equation balanced?

• Yes

• No

Tags

NGSS.MS-PS1-5

This is a pH scale of some common substances. Which substance would be considered slightly basic?

(a)  

Scientists commonly work with corrosive acids in the laboratory, being careful to wear gloves and safety goggles or respirators to protect their skin and airways. Other acids are much weaker and are even found in common foods and drinks. The following table lists the names, chemical formulas, and common uses for four different acids. Which of the statements below are true? Choose three correct answers.

• A molecule of sulfuric acid contains one hydrogen atom.

• Carbonic acid has three elements.

• There a total of 7 atoms in sulfuric acid.

• Acetic acid contains the most elements.

• Two molecules of Perchloric acid would contain 8 oxygen atoms.

Tags

NGSS.MS-PS1-1

Reference the photo of water droplets hanging from pine needles. Which statement correctly describes the forces acting on the droplets of water?

• Adhesion and cohesion cause the water molecules to stick together, forming a droplet. Adhesion causes the water to stick to the pine needle, preventing droplets from falling off.

• Adhesion causes the water molecules to stick together, forming a droplet. Cohesion causes the water to stick to the pine needle, preventing droplets from falling off.

• Cohesion causes the water molecules to stick together, forming a droplet. Adhesion causes the water to stick to the pine needle, preventing droplets from falling off.

• Cohesion causes the water molecules to stick together, forming a droplet. Adhesion and cohesion cause the water to stick to the pine needle, preventing droplets from falling off.

Four students categorize the following four foods as elements, compounds, homogeneous mixtures, and heterogeneous mixtures. Fill in the blank with the student who is correct.

(a)  

Four students were asked to compare cohesion and adhesion using a table. Identify which tables are correct. Check all that apply.

• A

• B

• C

• D

Tags

NGSS.MS-ESS2-4

Which of the following statements are true about the law of conservation of mass?

• The number of atoms on each side of the equation may not be the same.

• In a closed system, the mass of the reactants will equal the mass of the products.

• Mass of the products is greater than the mass of the reactants.

• The elements on the reactant side are different from the elements on the product side.

• Mass is neither created nor destroyed in chemical reactions.

Tags

NGSS.MS-PS1-5