Electrostatic Potential and Capacitance Part 2

A capacitor P with capacitance 10×10−6F is fully charged with a potential difference of 6.0 V and disconnected from the battery. The charged capacitor P is connected across another capacitor Q with capacitance 20×10−6F. The charge on capacitor Q when equilibrium is established will be α×10−5C (assume capacitor Q does not have any charge initially), the value of α is ____。