A capacitor has capacitance C. Is this information sufficient to know what maximum charge the capacitor can contain? If yes, what is this charge? If no, what other information is needed?

Charge on the capacitor is given by product of capacitance and potential difference across capacitor plates

Charge on the capacitor,

Where,

C is the capacitance of the capacitor

V is the potential on the capacitor

Therefore, without knowing the potential difference and only capacitance we cannot find out the maximum charge capacitor can contain.

∴ The following information is insufficient.