Question

in which state is oxygen at 0 degree celcius

Answer 1

Solid oxygen forms at normal atmospheric pressure at a temperature below 54.36 K (−218.79 °C, −361.82 °F).

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Answer 2

Oxygen forms solid itself at normal atmospheric pressure i.e. 1atm and  at a temperature below 54.36 K (−218.79 °C).

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