Properties of the wave after getting reflected:
1) Has same speed
2)Same frequency
3)Same wavelength
Only the direction changes
Properties of the wave after getting refracted
1) Speed decrease
2)Direction changes
3)Wavelength becomes shorter
So the distance of the wavefront becomes shorter...closer to each other but u have to make sure that the distance between each wave front is the same!! I attached a pic but it's not that accurate..i just want u to understand the idea
Hope u understood