The escape velocity is 2 x as much

Explanation

V_esc = SQRT(2GM/R) Mass (M) is twice and Radius (R) is ½. 2 and G are constants

V_esc = SQRT(1x1x2/(1/2))= SQRT( 4) = 2

1 has been substituted for everything that did not change and the change has been put in where variables changed