The correct order of `Delta_(i) H_(1)` values is:

Options

A. `He lt Ne gt Ar = Kr gt Xe gt Rn`
B. `He lt Ne lt Ar lt Kr lt Xe lt Rn`
C. `He gt Ne gt Ar gt Kr gt Xe gt Rn`
D. He= Ne gt Ar gt Kr gt Xe gt Rn`

Explanation

To determine the correct order of the first ionization enthalpy values (ΔiH₁), we need to consider the factors that influence ionization energy. Here’s a step-by-step solution:

### Step 1: Understand Ionization Energy
Ionization energy is the energy required to remove an electron from an isolated gaseous atom. The first ionization enthalpy (ΔiH₁) specifically refers to the energy required to remove the outermost electron.

### Step 2: Identify Trends in the Periodic Table
Ionization energy generally increases across a period (from left to right) due to increasing nuclear charge, which holds the electrons more tightly. Conversely, ionization energy decreases down a group (from top to bottom) because of increased distance between the nucleus and the outermost electrons and increased electron shielding.

### Step 3: Compare Elements
To establish the correct order of ΔiH₁ values, we need to compare the elements in question. For example, if we are comparing elements like Li, Na, K, Be, Mg, Ca, we can apply the trends identified in Step 2.

- **Group Trend**: As we move down a group (e.g., from Li to Na to K), the ionization energy decreases.
- **Period Trend**: As we move across a period (e.g., from Be to B to C), the ionization energy increases.

### Step 4: Write the Order
Based on the trends, we can write the order of ΔiH₁ values for the elements being compared. For example, if we compare Li, Be, Na, and Mg, the order would be:
- Be > Mg > Li > Na

### Step 5: Conclusion
The correct order of ΔiH₁ values can be concluded based on the periodic trends discussed.