About reaxff force field with no chemical reaction

Hello guys,
I have a system which consists of small gases such as hydrogen, carbon monoxide, carbon dioxide and water. For water, I used TIP4P/2005 model. For gases, fortunately, I found that there is a potential named ffield.reax.cho in the potentials folder.
Since I haven’t use reaxff before, and my system doesn’t require chemical reaction because I just want to investigate the diffusion of this system.
My question is that can I use pair_style reax/c to define the interactions between these gases with ffield.reax.cho potential and use fix nvt, nve to integrate velocity and position rather than fix qeq/reax?
If I can, then how can I define the interactions between gases and water? If I use lj/cut/coul/long, how can I get the epsilon and sigma for L-J parameters because there is no epsilon and sigma in ffield.reax.cho?
Thanks a lot for help.