Answer: 16 chips

Each RAM chip = $128 \times 8$ = 128 bytes (128 locations of 8-bit words).

Required capacity = 2048 bytes.

$$\text{No. of chips} = \frac{\text{Required capacity}}{\text{Chip capacity}} = \frac{2048}{128} = 16$$

So 16 chips of $128 \times 8$ are needed (arranged as $16 \times 128 = 2048$ bytes; 8-bit width matches, no width expansion needed — only depth expansion; needs 11 address lines, 7 for chip internal, 4 for chip select via decoder).