Question

part b
the students conducted a second experiment. they measured 100 ml of
water, density 1 g/cm³ and 100 ml of mineral oil, density 0.8 g/cm³
they poured the water into cup a and the oil into cup b. next they
added an ice cube to each cup. all but one statement is a valid
conclusion.
a ice is more dense than mineral oil
b ice has a density less than 1 g/cm³
c ice and liquid water have the same density but ice is
buoyant in water
d if oil and water are combined in one cup, the oil will
float on top of the water
(image: a jar labeled with layers: air, oil, water, golden syrup)

Explanation:

To solve this, we analyze each option using density and buoyancy principles:

• Option A: Ice sinks in oil? Wait, no—wait, in the experiment, ice is added to oil (Cup B) and water (Cup A). Wait, ice floats on water (so ice density < water density, which is 1 g/cm³, so B is valid). For oil (density 0.8 g/cm³), if ice sinks in oil, that would mean ice density > oil density. But wait, actually, ice has a density of about 0.917 g/cm³, which is more than oil's 0.8 g/cm³, so ice would sink in oil? Wait, no—wait, the diagram shows oil on top of water, so oil is less dense than water. Now, ice: ice floats on water (so ice density < 1 g/cm³). For oil (density 0.8 g/cm³), ice density (0.917) is more than oil's, so ice would sink in oil? Wait, but the option A says "Ice is more dense than mineral oil"—if ice sinks in oil, that's true. Wait, maybe I messed up. Let's check each option:
• Option B: Ice floats on water, so ice density < water density (1 g/cm³). So B is valid.
• Option C: Ice and liquid water do NOT have the same density. Ice is less dense than liquid water (that's why it floats). So C is the invalid statement.
• Option D: Oil density (0.8) < water density (1), so oil will float on water. So D is valid.

So the invalid statement is C.

Answer:

C. Ice and liquid water have the same density but ice is buoyant in water