Understanding Nitrogen Content in Chemical Fertilizers

Chemical fertilizers provide essential nutrients to plants to help them grow. Nitrogen (N) is one of the most important nutrients, crucial for leaf growth and protein formation. Different fertilizers contain varying amounts of nitrogen.

To find out which fertilizer has the highest nitrogen content, we need to calculate the percentage of nitrogen by mass in each chemical compound listed in the options. This is done by finding the ratio of the total atomic mass of nitrogen atoms in the molecule to the molar mass of the entire compound, then multiplying by 100%.

We will use the approximate atomic masses for calculation:

• Nitrogen (N): \(14.01 \text{ g/mol}\)
• Hydrogen (H): \(1.01 \text{ g/mol}\)
• Oxygen (O): \(16.00 \text{ g/mol}\)
• Calcium (Ca): \(40.08 \text{ g/mol}\)
• Potassium (K): \(39.10 \text{ g/mol}\)
• Sodium (Na): \(22.99 \text{ g/mol}\)

Calculating Nitrogen Percentage in Each Fertilizer

Let's calculate the percentage of nitrogen for each fertilizer option:

1. Ammonium Nitrate (\(\text{NH}_4\text{NO}_3\))

• Molar mass of \(\text{NH}_4\text{NO}_3\): \( (1 \times 14.01) + (4 \times 1.01) + (1 \times 14.01) + (3 \times 16.00) \) \( = 14.01 + 4.04 + 14.01 + 48.00 = 80.06 \text{ g/mol} \)
• Total mass of Nitrogen in \(\text{NH}_4\text{NO}_3\): The molecule contains two nitrogen atoms. \( = 2 \times 14.01 = 28.02 \text{ g/mol} \)
• Percentage of Nitrogen: \( \left(\frac{28.02}{80.06}\right) \times 100\% \approx 35.00\% \)

2. Calcium Nitrate (\(\text{Ca(NO}_3)_2\))

• Molar mass of \(\text{Ca(NO}_3)_2\): \( (1 \times 40.08) + 2 \times ((1 \times 14.01) + (3 \times 16.00)) \) \( = 40.08 + 2 \times (14.01 + 48.00) = 40.08 + 2 \times 62.01 = 40.08 + 124.02 = 164.10 \text{ g/mol} \)
• Total mass of Nitrogen in \(\text{Ca(NO}_3)_2\): The molecule contains two nitrogen atoms. \( = 2 \times 14.01 = 28.02 \text{ g/mol} \)
• Percentage of Nitrogen: \( \left(\frac{28.02}{164.10}\right) \times 100\% \approx 17.08\% \)

3. Potassium Nitrate (\(\text{KNO}_3\))

• Molar mass of \(\text{KNO}_3\): \( (1 \times 39.10) + (1 \times 14.01) + (3 \times 16.00) \) \( = 39.10 + 14.01 + 48.00 = 101.11 \text{ g/mol} \)
• Total mass of Nitrogen in \(\text{KNO}_3\): The molecule contains one nitrogen atom. \( = 1 \times 14.01 = 14.01 \text{ g/mol} \)
• Percentage of Nitrogen: \( \left(\frac{14.01}{101.11}\right) \times 100\% \approx 13.86\% \)

4. Sodium Nitrate (\(\text{NaNO}_3\))

• Molar mass of \(\text{NaNO}_3\): \( (1 \times 22.99) + (1 \times 14.01) + (3 \times 16.00) \) \( = 22.99 + 14.01 + 48.00 = 85.00 \text{ g/mol} \)
• Total mass of Nitrogen in \(\text{NaNO}_3\): The molecule contains one nitrogen atom. \( = 1 \times 14.01 = 14.01 \text{ g/mol} \)
• Percentage of Nitrogen: \( \left(\frac{14.01}{85.00}\right) \times 100\% \approx 16.48\% \)

Comparison of Nitrogen Content

Let's compare the calculated nitrogen percentages for each fertilizer:

From the table and calculations, it is clear that Ammonium nitrate contains the highest percentage of nitrogen among the given options.

Therefore, the chemical fertilizer that contains higher nitrogen is Ammonium nitrate.