Im looking for help with my chem homework

Question

Heptane and water do not mix, and heptane has a lower density (0.684 g/mL) than water (1.00 g/mL). A 100-mL graduated cylinder with an inside diameter of 3.04 cm contains 35.3 g of heptane and 38.1 g of water. What is the combined height of the two liquid layers in the cylinder? The volume of a cylinder is π r²h, where r is the radius and h is the height.



Answer 1

That they do not mix means that the volumes add and each volume can be found individually.

V_H = 35.3g (1ml/.684g) = 51.61 ml and V_W = 38.1 ml (density is 1 g/ml)

Total volume is 51.61 + 38.1 = 89.71 ml = 89.71 cm³

To find the height just divide the volume by the cross-sectional area. A = π(3.04 cm)²

I'll leave the rest to you. Take care.