Brainpop Ph Scale Worksheet Answers - Fill Online, Printable ... - Free Printable

Let's solve each question in the BrainPOP - pH Scale worksheet step by step, using the provided Word Bank and scientific knowledge.

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1. The term ________ refers to the chemical potential of hydrogen.

✔ Answer: pH

> Explanation: "pH" stands for *potential of hydrogen*, which measures the concentration of hydrogen ions (H⁺) in a solution.

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2. The pH ________ measures how ________ or basic a substance on a scale of 1 to 14. ________ measure from 1 to 7, while the ________ or alkaline side measures from 7 to 14.

✔ Answer:
- The pH scale measures how acidic or basic a substance on a scale of 1 to 14.
- Acids measure from 1 to 7, while the base or alkaline side measures from 7 to 14.

> Explanation: The pH scale ranges from 0 to 14. Values below 7 are acidic, 7 is neutral, and above 7 are basic (alkaline).

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3. Identify each as an acid (A) or a base (B).

| Substance | Answer |
|----------------------|--------|
| Lemon juice | A |
| Soap | B |
| Battery acid | A |
| Hydrochloric acid | A |
| Toothpaste | B |
| Vinegar | A |
| Baking soda | B |
| Floor cleaner | B |

> Explanation:
- Lemon juice: Citric acid → Acid
- Soap: Contains hydroxide ions → Base
- Battery acid: Sulfuric acid → Acid
- Hydrochloric acid: Strong acid → Acid
- Toothpaste: Contains fluoride and mild base → Base
- Vinegar: Acetic acid → Acid
- Baking soda: Sodium bicarbonate → Base
- Floor cleaner: Often contains ammonia → Base

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4. Really strong acids and bases are found at the ________ of the scale, while those near the ________ are weaker. Right in the middle at exactly 7, or pH ________, you have pure water.

✔ Answer:
- Really strong acids and bases are found at the ends of the scale, while those near the center are weaker. Right in the middle at exactly 7, or pH neutral, you have pure water.

> Explanation: The extremes (0–1 and 13–14) are very strong acids/bases; center (around 7) is neutral. Pure water has a pH of 7.

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5. Acids contain ________ ions (H⁺), while bases contain ________ (OH⁻) ions. Ions are atoms that have either lost or gained ________. In bases you find hydroxyl ions, which have ________ electrons. Hydrogen ions found in acids are ________ that have had an electron knocked off, which is why these ions are always trying to get the lost electrons back. When you put a metal in acid, the metal starts to ________.

✔ Answer:
- Acids contain hydrogen ions (H⁺), while bases contain hydroxyl (OH⁻) ions.
- Ions are atoms that have either lost or gained electrons.
- In bases you find hydroxyl ions, which have gained electrons.
- Hydrogen ions found in acids are atoms that have had an electron knocked off...
- When you put a metal in acid, the metal starts to dissolve.

> Explanation:
- H⁺ is a proton (hydrogen ion).
- OH⁻ is the hydroxyl ion (has extra electron → negatively charged).
- Ions form when atoms lose/gain electrons.
- Metals react with acids to produce hydrogen gas and dissolve.

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6. Bases have the power to ________ acids. The hydroxyl ion ________ its electron with the hydrogen ion. The H⁺ from the hydrogen ion and the OH⁻ from the hydroxyl ion bond together to form H₂O, which is ________ with pH neutral. Different types of ________ are formed depending on the types of acids and bases involved in the reaction.

✔ Answer:
- Bases have the power to neutralize acids.
- The hydroxyl ion shares its electron with the hydrogen ion.
- The H⁺ and OH⁻ bond to form H₂O, which is neutral with pH neutral.
- Different types of salts are formed...

> Explanation:
- Neutralization is the reaction between acid and base.
- Water (H₂O) is formed when H⁺ and OH⁻ combine.
- Salt is a product of acid-base reactions (e.g., NaCl from HCl + NaOH).

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7. When Moby poured the baking soda (a base) into the vinegar (an acid), a reaction occurred. Salt, water, and ________ were produced by the reaction.

✔ Answer: Carbon dioxide

> Explanation: This is a classic acid-base reaction:
>
> Vinegar (acetic acid) + Baking soda (sodium bicarbonate) → Sodium acetate (salt) + Water + Carbon dioxide gas

So, carbon dioxide is released as bubbles.

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8. ________ are substances that can block changes in their pH for period of time. You can find them on buffered aspirin, which keeps your ________ ________ from dissolving the medicine too quickly. Buffers are made by combining ________ acids and bases. Buffers also are found in our body to keep our the pH of our ________ at or around 7.4.

✔ Answer:
- Buffers are substances that can block changes in their pH...
- ...which keeps your stomach acid from dissolving the medicine too quickly.
- Buffers are made by combining weak acids and bases.
- ...keep our the pH of our blood at or around 7.4.

> Explanation:
- Buffers resist pH changes.
- Buffered aspirin prevents irritation in stomach.
- Weak acids/bases are used because they don’t fully dissociate, allowing equilibrium to buffer pH.
- Blood pH must stay ~7.4 for proper function.

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9. Most science labs have pH paper, which is paper that has been soaked in a special chemical ________. They turn ________ in an acid and ________ in a base. By comparing the color of the pH paper to a chart, you can determine how ________ an acid or base is.

✔ Answer:
- ...soaked in a special chemical indicator.
- They turn red in an acid and blue in a base.
- ...you can determine how strong an acid or base is.

> Explanation:
- pH indicators change color based on pH.
- Common ones like litmus paper turn red in acid, blue in base.
- Color intensity helps estimate strength.

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10. Constant reactions between acids and bases keep our ________ from being too acidic or too alkaline.

✔ Answer: environment

> Explanation: In biological systems (like blood), buffers maintain stable pH. But here, “environment” fits best in context — meaning the internal environment (like blood or cells). However, if we consider broader context, it could be body or blood.

But given the word bank and sentence structure:

✔ Best fit: Blood

Wait — let’s check word bank: Blood, Environment, Body? Only Blood is listed.

So correct answer: blood

> ✔ Final Answer: blood

> Explanation: The body uses acid-base balance (buffers) to keep blood pH around 7.4.

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## ✔ Final Answers Summary:

1. pH
2. scale, acidic, Acids, base
3.
- Lemon juice: A
- Soap: B
- Battery acid: A
- Hydrochloric acid: A
- Toothpaste: B
- Vinegar: A
- Baking soda: B
- Floor cleaner: B
4. ends, center, neutral
5. hydrogen, hydroxyl, electrons, gained, atoms, dissolve
6. neutralize, shares, neutral, salts
7. carbon dioxide
8. Buffers, stomach acid, weak, blood
9. indicator, red, blue, strong
10. blood

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✔ All answers are filled in using the Word Bank and scientific reasoning. Let me know if you'd like this formatted as a completed worksheet!