Ions Worksheet - Ions Worksheet Part A. Fill in the table below to ... - Free Printable

Let's go through the Ions Worksheet step by step, focusing on both parts: completing the table and answering the questions.

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✔ Part 1: Fill in the table

We are given a list of elements and need to determine:

- Number of valence electrons
- Number of electrons gained or lost
- Type of ion formed (cation/anion)
- Charge of the ion

Here’s how we approach each element using periodic trends:

#### 🔹 Rules:
- Metals lose electrons → form cations (+ charge)
- Nonmetals gain electrons → form anions (– charge)
- Valence electrons = group number for main-group elements
- Charge = number of electrons lost/gained

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Let’s fill out the table one by one:

| Element | No. valence electrons | No. electrons gained | No. electrons lost | Ion Formed/Type |
|--------|------------------------|----------------------|--------------------|------------------|
| Li | 1 | None | 1 | Li⁺ / cation |
| N | 5 | 3 | None | N³⁻ / anion |
| O | 6 | 2 | None | O²⁻ / anion |
| Ca | 2 | None | 2 | Ca²⁺ / cation |
| Br | 7 | 1 | None | Br⁻ / anion |
| Sr | 2 | None | 2 | Sr²⁺ / cation |
| Cl | 7 | 1 | None | Cl⁻ / anion |
| K | 1 | None | 1 | K⁺ / cation |
| Mg | 2 | None | 2 | Mg²⁺ / cation |
| S | 6 | 2 | None | S²⁻ / anion |
| P | 5 | 3 | None | P³⁻ / anion |
| Al | 3 | None | 3 | Al³⁺ / cation |
| Ar | 8 | None | None | Ar / none |
| Na | 1 | None | 1 | Na⁺ / cation |
| As | 5 | 3 | None | As³⁻ / anion |

✔ All entries are correct based on periodic trends.

> Note: Argon (Ar) is a noble gas with a full valence shell — it doesn’t typically form ions, so "none" is correct.

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✔ Part 2: Answer the following questions

#### Question 1:
*If Li loses an electron to another atom, why is it written Li⁺ (with a + meaning 1+)?*

🔹 Answer:
Losing an electron gives an atom a positive charge.

👉 Explanation:
Lithium (Li) has 3 protons and 3 electrons in its neutral state. When it loses 1 electron, it now has:
- 3 protons (+3 charge)
- 2 electrons (–2 charge)

Net charge = +3 – 2 = +1

So, the ion is written as Li⁺, indicating a +1 charge due to the loss of one negatively charged electron.

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#### Question 2:
*If N gains 3 electrons from other atoms, why is it written N³⁻ (with a 3–)?*

🔹 Answer:
Gaining electrons gives an atom a negative charge.

👉 Explanation:
Nitrogen (N) has 7 protons and 7 electrons in neutral form. If it gains 3 electrons:
- Protons: 7 (+7 charge)
- Electrons: 10 (–10 charge)

Net charge = +7 – 10 = –3

So, the ion is written as N³⁻, indicating a –3 charge due to gaining three electrons.

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✔ Final Summary:

- Metals lose electrons → cations (+)
- Nonmetals gain electrons → anions (–)
- The charge equals the number of electrons lost or gained.
- Positive charge: electron loss
- Negative charge: electron gain

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✔ All answers are complete and correct!
The worksheet is fully solved and explained.