Acids and Bases

Notes

During a science fair, Rohan demonstrates how both lemons and batteries can power a small LED light. What do lemons and batteries have in common that allows this?

• They are both bases

• They are both neutral substances

• They are both acids

• They both contain salt

Answer explanation

Lemons and batteries are both acids, not bases, neutral substances, or containing salt.

Tags

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During a science project, Noah and Avery are discussing the properties of household items. They wonder, what is a common property of baking soda and soap?

• They are both acids

• They are both salts

• They are both bases

• They are both neutral substances

Answer explanation

Both baking soda and soap are considered bases, which means they have a pH greater than 7 and can neutralize acids.

What happens to a salt solution when it gains or loses electrons?

• It becomes a neutral substance

• It becomes a base

• It becomes an acid

• It forms an ion

Answer explanation

When an atom gains or loses electrons, it forms an ion by becoming positively or negatively charged.

During a science fair, Charlotte demonstrates the properties of substances by adding them to water. Which of the following properties is she showcasing when a substance releases hydrogen ions (H+) in solution?

• They release hydroxide ions (OH-) in solution

• They release hydrogen ions (H+) in solution

• They have formulas whose first element is always O

• They are typically found in batteries only

Answer explanation

Acids release hydrogen ions (H+) in solution, making it a characteristic of acids.

Tags

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During a chemistry class, Sophia and Arjun were tasked with creating a list of chemical formulas for common acids. Sophia asks, 'What is the chemical formula for sulfuric acid?'

During a science class, Daniel was curious to know where hydrochloric acid is naturally found. Can you help him?

• In soap

• In the human stomach

• In batteries

• In baking soda

Answer explanation

Hydrochloric acid is naturally found in the human stomach, where it aids in the digestion process.

During a cooking class, Mia accidentally tasted a lemon juice and described its taste. What is a common property of acids like lemon juice that can be identified by taste?

• Acids taste sweet.

• Acids taste salty.

• Acids taste sour.

• Acids taste bitter.

Answer explanation

Acids taste sour, which is a common property that can be identified by taste.

During a science fair, Benjamin is demonstrating the properties of acids and bases. He asks the audience to identify which of the following items he has on his table is a base.

• Vinegar

• Lemon juice

• Baking soda

• Orange juice

Answer explanation

Baking soda is an example of a base because it can accept protons or donate electrons in a chemical reaction.

Zoe is conducting a chemistry experiment and needs to create a solution of sodium hydroxide. Which chemical formula should she use?

• Ca(OH)2

• NaCl

• NaOH

• H2SO4

Answer explanation

The correct chemical formula for sodium hydroxide is NaOH, as it consists of one sodium atom (Na) and one hydroxide ion (OH).