Question

Imagine a hypothetical fluid made only of helium nuclei (practically, just liquid ionized helium), and let's say, it's seen that it floats on water, like oil. A similar fluid made of uranium${(}_{92}^{238}U)$ nuclei, what will happen to it once put in the same water?

• A. It will float above water, just like in helium's case
• B. It will dissolve in water
• C. It will sink below water and settle at the bottom
• D. It's hard to infer from given information.

Answer 1

The correct option is A

It will float above water, just like in helium's case

If body A (by body I mean solid or liquid) has density ${\rho }_A$, and liquid B has density ${\rho }_B$ , then A will float on B if ${\rho }_A$<${\rho }_B$ , mix if ${\rho }_A={\rho }_B$ , and sink if ${\rho }_A$>${\rho }_B$ . Denser bodies sink.

If helium floats on water, it means it's density is lower than water. But all nuclei have the same density. Which means liquid uranium nuclei will have the same density as liquid helium nuclei. Which in turn means, the uranium nuclei liquid's density will be lower than water, just like helium.

The ${}_{92}^{238}U$ nuclei liquid will float on water, just like the much lighter liquid, because they have the same density.