Which set of the minerals is absorbed as cations by plants?

Options

A. S and Fe
B. Mo and Fe
C. B and Zn
D. Mn and B

Answer

To determine which set of minerals is absorbed as cations by plants, we can analyze the options provided in the question. Here’s a step-by-step solution:

### Step 1: Understand Cations
Cations are positively charged ions. Therefore, we need to identify which minerals are absorbed by plants in their cationic form.

### Step 2: Analyze Each Mineral
1. **Sulfur**: Sulfur is absorbed as sulfate ions (SO4^2-), which are negatively charged (anions). Thus, it is not a cation.

2. **Molybdenum**: Molybdenum is absorbed as molybdate ions (MoO4^2-), which are also negatively charged (anions). So, it is not a cation.

3. **Iron**: Iron is absorbed as ferric ions (Fe^3+), which are positively charged (cations). This qualifies as a cation.

4. **Boron**: Boron is absorbed in the form of borate ions (BO3^3- or B4O7^2-), which are negatively charged (anions). Therefore, it is not a cation.

5. **Zinc**: Zinc is absorbed as Zn^2+, which is a positively charged ion (cation). This qualifies as a cation.

6. **Manganese**: Manganese is absorbed as Mn^2+, which is also a positively charged ion (cation). This qualifies as a cation.

### Step 3: Identify the Correct Set
From the analysis:
- Cations: Iron (Fe^3+), Zinc (Zn^2+), and Manganese (Mn^2+).
- Anions: Sulfur (SO4^2-), Molybdenum (MoO4^2-), and Boron (BO3^3-).

Since we are looking for a set of minerals that are absorbed as cations, the correct answer would include Iron, Zinc, and Manganese.

### Conclusion
The set of minerals absorbed as cations by plants includes Iron (Fe^3+), Zinc (Zn^2+), and Manganese (Mn^2+).

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