How soluble or corrosive is Uranium and Plutonium in hot salt water?

[Fledermaus]

From what I have read, Plutonium is very reactive and will decompose easily.

[slackmaster]

1. Neither exists in a metallic state in the reactors in Japan, if that's what you're thinking about

The fuel consists of oxides of the metals.

[Fledermaus]

2. Even when the fuel has melted?

[slackmaster]

4. Uranium dioxide melts at 2865 °C

Whether it would reduce to metal at that point, I don't know, but I don't believe the messes are expected to get that hot.

The zirconium tubes that contain the pellets are expected to melt in a full meltdown.

[jpak]

3. Nobody knows - this unprecedented

The oxides are pretty insoluble - but if they are transformed into or leached by chlorides, sulfates, nitrates, carbonates - who knows?

[Fledermaus]

5. My impression is that the sea water is going through once.

And my impression is that there has been some core melting.

[jpak]

6. Then there is ample opportunity for lots of unprecedented chemistry to happen

and potential for mobile radionuclides to accumulate in that water....

[thereismore]

7. I think the danger is zirconium cladding reacting with steam (i.e. burning) and taking some of

the radioactive content up into the air. Radioactive gases first, and then maybe particles of the solid material.