The molar volume of a gas at STP is 22.4 L/mol. This means that 1 mole of any gas at STP occupies 22.4 L. Therefore, 1.50 moles of CH4 at STP will occupy:

$$V = 1.50 \text{ mol} \times 22.4 \text{ L/mol} = 33.6 \text{ L}$$

Therefore, 1.50 moles of CH4 at STP will occupy 33.6 L.