Acid and Base

Multiple Choice

Why are acids and bases important for living organisms?

• They help in digestion and other bodily functions.

• They are only used in industrial processes.

• They have no role in living organisms.

• They are harmful to all forms of life.

Multiple Choice

Why is it important for blood to maintain a pH close to 7.4?

• Because enzymes in the blood work best at this pH

• Because it prevents blood from clotting

• Because it helps in digestion

• Because it keeps the blood red

Open Ended

How does the alkalinity of saliva contribute to dental health?

Multiple Choice

Which of the following is neutralized by soap according to the images?

• Acidic sweat

• Alkaline saliva

• Blood pH

• Acidic food

Fill in the Blanks

All of these real-life situations are controlled by

chemistry.

Open Ended

Explain the process of neutralisation and write the chemical equation for it.

Multiple Select

Which of the following are learning objectives for the topic of acids and bases?

• Identify acids, bases, and alkalis using their characteristic properties

• Describe how acids react with metals, bases, and carbonates

• Use indicators to determine whether a substance is acidic or alkaline

• Explain the meaning of pH and compare acidity/alkalinity using universal indicator

Multiple Choice

Which of the following is NOT a characteristic of acids?

• Acids release H+ ions in water.

• Acids turn blue litmus red.

• Acids conduct electricity because of H+ ions.

• Acids feel slippery and taste bitter.

Multiple Choice

Which of the following statements is correct regarding the pH value of acids?

• Acids have a pH value greater than 7.

• Acids have a pH value less than 7.

• Acids have a pH value equal to 7.

• Acids do not have a pH value.

Fill in the Blanks

A salt is formed when the metal ions replace the

ions in an acid.

Multiple Select

Which of the following are true about alkalis?

• Alkalis are soluble bases.

• Alkalis release OH- ions in water.

• Alkalis turn blue litmus red.

• Alkalis conduct electricity because of OH- ions.

Multiple Choice

What does pH stand for?

• Potential of hydrogen or power of hydrogen

• Percentage of hydrogen

• Presence of hydroxide

• Purity of hydrogen

Multiple Select

Which of the following statements about acidic, neutral, and alkaline solutions are correct?

• Acidic solutions have more hydrogen ions than hydroxide ions.

• Neutral solutions have equal amounts of hydrogen and hydroxide ions.

• Alkaline solutions have more hydroxide ions than hydrogen ions.

• Acidic solutions have more hydroxide ions than hydrogen ions.

Multiple Choice

Which of the following substances is considered neutral on the pH scale?

• Coffee

• Pure water

• Lemon juice

• Baking soda

Fill in the Blanks

A solution with a pH value less than 7 is considered

.

Multiple Choice

What are some consequences if blood pH changes significantly from 7.4?

• Enzymes stop working properly

• Cells function better

• Oxygen transport becomes less efficient

• Organs like the brain and heart can be affected

Multiple Choice

What is the role of hydrochloric acid (HCl) in your stomach?

• It helps digest food and kills bacteria.

• It neutralizes stomach acid.

• It protects tooth enamel.

• It makes saliva alkaline.

Open Ended

Compare the pH of stomach acid to battery acid. Why is this similarity significant for our understanding of acids and bases in the human body?

Fill in the Blanks

The symbol equation for neutralization is H+ (aq) +

(aq) → H2O (l).

Multiple Choice

When an acid and a base react, what is formed during the neutralization reaction?

• Salt

• Water

• Carbon dioxide

• Oxygen

Open Ended

Explain how the alkalinity of saliva helps prevent tooth decay.

Multiple Select

Which of the following statements about saliva is/are correct?

• Saliva is slightly alkaline.

• Saliva helps neutralize acids in the mouth.

• Saliva has a pH similar to stomach acid.

• Saliva protects tooth enamel from dissolving.