Standard Enthalpy Change Symbol?

Factual Questions
1

I’m currently doing A-Level chemistry, and have reached the lovely part where you have to calculate standard enthalpy changes using Hess’s Law.

For the enthalpy change, we write [delta]H and then another symbol if it’s a standard enthalpy change. The other symbol is a mystery to me, it looks like Theta with the line going right through it, or more like a capital Phi, but on it’s side.

Is there anyone who knows what this symbol is? Is it actually a greek letter, or just another symbol we use in chemistry. In either case, is there a symbol for it in Word, because currently in my assignments, I’m either drawing it on afterwards, or simply using theta, which isn’t really correct.

Can someone please help me?

2

According to Concepts in Physical Chemistry by Peter Atkins [page 316], it’s just the symbol used to denote variables in the standard state, and also notes that a simple circle (which I’m used to using) is also acceptable. I’ve never seen it used anyplace else, and Atkins suggests no other name than “a superscript o- sign” (imagine that line through the o and the whole thing superscripted).

3

I’ve never seen anything other than just an [sup]o[/sup], but maybe that’s just a phenomenon of more recent textbooks…