Order of operations and evaluating expressions.

To evaluate the expression \( \frac{16}{n} + 2^3 - 10 \) when \( n = 8 \), we will follow the order of operations (PEMDAS/BODMAS):

1. **Substitute the value of n**:
\[
n = 8 \Rightarrow \frac{16}{8} + 2^3 - 10
\]

2. **Evaluate the division**:
\[
\frac{16}{8} = 2
\]
So our expression now looks like:
\[
2 + 2^3 - 10
\]

3. **Evaluate the exponent**:
\[
2^3 = 2 \times 2 \times 2 = 8
\]
Now substitute back into the expression:
\[
2 + 8 - 10
\]

4. **Now perform the addition and subtraction from left to right**:
- First add:
\[
2 + 8 = 10
\]
- Then subtract:
\[
10 - 10 = 0
\]

Thus, the value of the expression when \( n = 8 \) is \( \boxed{0} \).