1. Identify the element from atomic number

Atomic number $29$ corresponds to copper, Cu.

2. Write the electronic configuration of the neutral atom

For copper:

$\mathrm{Cu}: [Ar] \, 3d^{10}4s^1$

3. Find the configuration of the divalent ion

A divalent ion is $\mathrm{Cu^{2+}}$. Electrons are removed first from $4s$, then from $3d$:

$\mathrm{Cu^{2+}}: [Ar] \, 3d^9$

4. Consider aqueous solution

In aqueous solution, $\mathrm{Cu^{2+}}$ forms hydrated complexes, but for magnetic moment we need the number of unpaired electrons in $3d^9$.

For $3d^9$, the number of unpaired electrons is:

$n = 1$

5. Use spin-only magnetic moment formula

$\mu = \sqrt{n(n+2)}\ \text{BM}$

Substitute $n=1$:

$\mu = \sqrt{1(1+2)} = \sqrt{3}\ \text{BM}$

$\mu \approx 1.73\ \text{BM}$

6. Integer answer

Since the question is of integer type, the value is taken as nearest integer:

$\boxed{2}$

7. Comparison with stored answer

Stored correct answer = $2$.

Our derived integer answer also is $2$, so they agree.