Acids, Bases, and Salts Quiz
27 Questions
0 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to Lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What is the correct observation when red litmus paper is dipped into a 20% sodium hydroxide solution?

  • Red litmus paper turns blue (correct)
  • Red litmus paper turns red
  • Red litmus paper remains unchanged
  • Red litmus paper turns green

When a student adds 2 ml of water to 2 ml of acetic acid in a test tube, what is the likely observation?

  • The solution becomes light orange
  • Acetic acid floats over the surface of water
  • Water floats over the surface of acetic acid
  • The acetic acid dissolves readily in water (correct)

After adding 4 ml of acetic acid to 4 ml of distilled water in a test tube, what does the student observe after leaving it to settle for about 10 minutes?

  • A clear colorless solution (correct)
  • A layer of water over the layer of acetic acid
  • A layer of acetic acid over the layer of water
  • A precipitate settling at the bottom of the test tube

How can a student test for the gas liberated when hydrochloric acid reacts with an active metal?

<p>By observing the liberation of hydrogen gas (B)</p> Signup and view all the answers

Which pH value indicates a stronger acid, pH=5 or pH=2?

<p>pH=2 (A)</p> Signup and view all the answers

What is the solution that reacts with crushed egg shells to give a gas that turns lime milky?

<p>HCl (C)</p> Signup and view all the answers

Why does tooth decay start when pH of mouth is lower than 5.5?

<p>The acid produced by bacteria attacks the enamel at this pH level (C)</p> Signup and view all the answers

When fresh milk changes into curd, will its pH value increase or decrease? Why?

<p>The pH value will decrease due to the formation of lactic acid. (D)</p> Signup and view all the answers

Why does the flow of acid rainwater into a river make the survival of aquatic life difficult?

<p>Acid rainwater decreases the pH of the river water (C)</p> Signup and view all the answers

How does the flow of acid rain water into a river make the survival of aquatic life difficult?

<p>It lowers the pH of the river water. (C)</p> Signup and view all the answers

Which observation is true about a dilute solution of acetic acid?

<p>It has a low pH value. (B)</p> Signup and view all the answers

What happens to the pH value of an aqueous solution when an acid and a base are mixed together?

<p>The pH value remains unchanged. (A)</p> Signup and view all the answers

Why does a solution react with crushed egg shells to produce a gas that turns lime milky?

<p>Due to the presence of hydrochloric acid (HCl). (A)</p> Signup and view all the answers

What gas is produced when a solution reacts with crushed eggshells to turn lime milky?

<p>HCl (D)</p> Signup and view all the answers

What happens to the pH value when fresh milk changes into curd (yogurt)?

<p>Decreases due to the formation of lactic acid (A)</p> Signup and view all the answers

Why does the flow of acid rain water into a river make the survival of aquatic life difficult?

<p>It lowers the pH of the river water (A)</p> Signup and view all the answers

Which observation is true about a dilute solution of acetic acid?

<p>Turns blue litmus paper red (C)</p> Signup and view all the answers

What is the likely observation when a student tests for the gas liberated when hydrochloric acid reacts with an active metal?

<p>Formation of a colorless, odorless gas (D)</p> Signup and view all the answers

What is the correct observation when red litmus paper is dipped into a 20% sodium hydroxide solution?

<p>Turns blue (C)</p> Signup and view all the answers

What can a student observe when red litmus paper is dipped into a 20% sodium hydroxide solution?

<p>The red litmus paper turns blue (C)</p> Signup and view all the answers

What happens when a student adds 2 ml of water to 2 ml of acetic acid in a test tube?

<p>The acetic acid dissolves readily in water (B)</p> Signup and view all the answers

After adding 4 ml of acetic acid to 4 ml of distilled water in a test tube, what does the student observe after leaving it to settle for about 10 minutes?

<p>A clear colorless solution (C)</p> Signup and view all the answers

How can a student test for the gas liberated when hydrochloric acid reacts with an active metal?

<p>By placing a lighted match stick near the gas to check for a pop sound (A)</p> Signup and view all the answers

Which observation is true about a dilute solution of acetic acid?

<p>It smells like vinegar and turns red litmus blue (D)</p> Signup and view all the answers

Why does tooth decay start when pH of mouth is lower than 5.5?

<p>Acid produced in the mouth attacks the enamel (C)</p> Signup and view all the answers

Why does flow of acid rain water into a river make the survival of aquatic life difficult?

<p>Decreases the concentration of dissolved oxygen in the river water (A)</p> Signup and view all the answers

What is the correct observation when red litmus paper is dipped into a 20% sodium hydroxide solution?

<p>(I), (II) and (IV) (A)</p> Signup and view all the answers
Use Quizgecko on...
Browser
Browser