Acid, Base, PH - SC.8.P.8.8

Distilled water contains only water molecules. Any minerals or other compounds are removed in the distilling process. What is the pH of distilled water?

• 7
• 3
• 6
• 10

Each unit on the pH scale, as shown in the illustration below, represents a ten times change in concentration. For example, an acidic solution with a pH of 5 is ten times stronger than an acidic solution with a pH of 6. Likewise, a basic solution with a pH of 9 is ten times stronger than one with a pH of 8. Which pH values would represent a difference of 100 times in concentration?

• pH 8 and pH 10
• pH 4 and pH 9
• pH 6 and pH 7
• pH 1 and pH 5

The illustration below lists the pH of various substances. Which of the substances below is the closest to neutral pH?

• ammonia
• milk
• milk of magnesia
• vinegar

Look closely at the illustration below showing where the compound sodium hydroxide falls on the pH scale. What type of compound is sodium hydroxide?

• a salt
• an acid
• an element
• a base

The Swedish scientist Svante Arrhenius defined an acid as a substance that dissolves in water to release hydrogen ions into the solution, as shown in the illustration below. When hydrochloric acid (HCl) is dissolved in distilled water, ions of which two elements are released into the solution?

• hydrogen and oxygen
• hydrogen and salt
• hydrogen and chlorine
• sodium and chlorine

Tags

NGSS.MS-PS1-2

Alvaro has a beaker containing an unknown solution which he is trying to identify. When he placed a strip of magnesium (Mg) metal into the solution, it fizzed vigorously until the magnesium was used up. What type of solution does Alvaro most likely have?

• a salt
• distilled water
• an acid
• a base

Tags

NGSS.MS-PS1-2

Acid rain occurs in some regions on Earth and has a negative impact on plants and animals. Normal rainwater has a pH between 5.5 and 6. Which of the following is most likely to be the pH of rainwater that is classified as acid rain?

• pH of 6
• pH above 7
• pH of 7
• pH below 5

Tags

NGSS.MS-PS1-2

Litmus paper is a special type of paper treated with an indicator that changes color in the presence of an acid or a base. Red litmus paper is used to test for the presence of a base and turns blue in a basic solution. Suppose that a student uses red litmus paper to test solutions of four different pHs. Which of the following solutions would turn red litmus paper blue?

• solution at pH 9
• solution at pH 5
• solution at pH 2
• solution at pH 7

Human blood has a pH between 7.38 and 7.42. What can you conclude about human blood?

• It is slightly acidic.
• It is strongly acidic.
• It is neither acidic nor basic.
• It is slightly basic.

Tags

NGSS.HS-LS1-3

In a neutralization reaction, an acid and a base neutralize each other. Water is one of two products that are produced from the neutralization reaction. What is the other product?

• a gas
• a metal
• a protein
• a salt