Answer
Particle 1 has a negative charge.
Particle 2 has a positive charge.
Work Step by Step
$F = q~v\times B$
By the right hand rule, a particle would move clockwise if it had a positive charge, and a particle would move counter-clockwise if it had a negative charge.
Since particle 1 is moving counter-clockwise, it must have a negative charge.
Since particle 2 is moving clockwise, it must have a positive charge.
