what is capacitor cv
Q = Total Charge stored in the capacitor = C x V or CV = Capacitance x Voltage across the capacitor. The time is specified to reveal how much charge remains after the given time, say after 2 minutes.
Temperature affects the performance.
All capacitors suffers from leakage, i.e. DC current flows through it, between micro to nano amperes for off-the-shelve discrete capacitors.
Rated voltage suggests the nominal voltage to use.
Other specification like loss angle etc are for information on the phasor and matching with inductors in some power electronics concerning AC quality.