Hello Rizwan,
You don't mention any units in your expression. Can I guess it's for
ice at 0 C and expressed in J per kmol per Kelvin ?
I don't think the British units system managed to mess up the kmol too, so all you have to do is convert Joules to British dingdongs, so e.g.
if 1 Joule is 0.000947817 BTU,
and 1 K is 9/5 F (+ some constant) multiply by 0.000947817 and divide by 9/5. That's all.
But if you want to
mangle it further, you still have to divide by the molar weight to get ##\approx## 0.5
BTU/lbm/F
PS why do I have to google that for you? You can find such conversions all over the place !