`" The value of n in "Be_(3) Al_(n)(Si_(6)O_(18)) is _________.

Answer

To find the value of \( n \) in the formula \( \text{Be}_3 \text{Al}_n (\text{Si}_6 \text{O}_{18}) \), we can follow these steps:

### Step 1: Understand the Chemical Formula
The given formula is \( \text{Be}_3 \text{Al}_n (\text{Si}_6 \text{O}_{18}) \). This indicates that we have 3 beryllium (Be) atoms, \( n \) aluminum (Al) atoms, and a silicate structure containing 6 silicon (Si) atoms and 18 oxygen (O) atoms.

### Step 2: Identify the Known Values
From the video transcript, we can see that the correct formula for the compound is actually \( \text{Be}_3 \text{Al}_2 (\text{Si}_6 \text{O}_{18}) \). This means that the number of aluminum atoms in the compound is 2.

### Step 3: Compare the Formulas
Now, we can compare the two formulas:
- Given: \( \text{Be}_3 \text{Al}_n (\text{Si}_6 \text{O}_{18}) \)
- Correct: \( \text{Be}_3 \text{Al}_2 (\text{Si}_6 \text{O}_{18}) \)

By comparing the coefficients of aluminum in both formulas, we can see that \( n \) must be equal to 2.

### Step 4: Conclusion
Thus, the value of \( n \) in the formula \( \text{Be}_3 \text{Al}_n (\text{Si}_6 \text{O}_{18}) \) is:

\[ \boxed{2} \]

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