Tan – most scientific studies have shown that for strength, focus on at least 2 working sets (not counting warm ups) with weights that you can get between 3 to 6 reps from. But with this amount of weight, you'll need many warm up sets so 5 sets of 5 reps is about right.
For muscle growth, 8 to 10 reps is usually the target, with 3 or 4 working sets. Usually, you only need one or 1 warm up sets with this weight.
It also varies by exercise. For example, for calf work, you'll want to approximately double the above reps for target.
Keep in mind that each person responds differently, and that not every is statistically in the middle of the bell curve.