1. **State the problem:** A party host bought 8 bottles of sparkling water, each containing 1 liter. We need to find the total amount of sparkling water in milliliters. 2. **Recall the conversion formula:** 1 liter = 1000 milliliters. 3. **Calculate total volume in liters:** $$8 \times 1 = 8 \text{ liters}$$ 4. **Convert liters to milliliters:** $$8 \text{ liters} \times 1000 \frac{\text{milliliters}}{\text{liter}} = 8000 \text{ milliliters}$$ 5. **Final answer:** The party host bought **8000 milliliters** of sparkling water.