Bronze Yellow vs Nuclear Yellow

How close are they?

ΔE 31.1, loose: different enough that you should pick on purpose. Nuclear Yellow is a little darker, more saturated, warmer than Bronze Yellow.

Can I use Nuclear Yellow instead of Bronze Yellow?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 31). Nuclear Yellow is a little darker, more saturated, warmer than Bronze Yellow.

Can I use Bronze Yellow instead of Nuclear Yellow?

The same difference applies the other way round: Bronze Yellow is a little lighter, more muted, cooler.

ΔE is the colour difference between our two swatch estimates: under about 6 is close, over about 15 is loose. Real paints also differ in finish, coverage and how they thin, so test before you commit.