Answer: STP stands for standard temperature and pressure and refers to conditions of 273K (0 degree centigrade) at 760mmHg.
Explanation: Temperature, T1= 273 + 22= 295K; Pressure, P1= 763mmHg; Volume, V1= 50mL; T2= 273K; P2= 760mmHg; V2= ?
P1*V1/ T1 = P2*V2/ T2
V2= P1*V1*T2/P2*T1
V2= 763*50*273/760*295
∴ V2= 10414950/224200 = 46.45mL