Neon Ions Acceleration in Tube w/20kN/C Field

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A section of an advertising sign consists of a long tube filled with neon gas having electrodes inside at both ends. A uniform electric field of 20 kN/C is set up between the electrodes, and neon ions accelerate along the length of the tube. Given that the ions each have a mass of 3.35 X 10-26kg and are singly ionized, determine their acceleration.

E = 2000 N/C
m = 3.35 x 10-26kg

I'd like to ask if my answer below makes sense, but I have a feeling that my acceleration is much to high! Please let me know if I am incorrect and why.

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20 kN/C is 20 000 N/C, not 2000. Aside from that, your work is correct: ions in advertising signs really do experience huge accelerations. If you plug in a reasonable value for the length of the tube, you'll see that despite the large acceleration, the neon ions don't even reach relativistic speeds. (Electrons in cathode ray tubes, however, do; those in old TV sets reach approx. 30% the speed of light.)