Would you be disadvantaged if you do a Chemistry degree without a Physics A level? How much does the Physics A level help you in your Chemistry degree?
Also, how much Physics is there in a Chemistry degree?
Physical chemistry contains a lot of what you would otherwise call physics, especially any modules involving quantum mechanics. I'd say that after Chemistry and Maths, physics would be the best choice to take at A-level to benefit a chemistry degree.
After maths, I think it's the second most useful subject to have for tackling university level chemistry. The physical chemistry course will make use of a lot of it i.e. waves, quantum, and the classical mechanics knowledge is useful for when you study how CM blurs into quantum at the small scale.
There is a lot of physics in chemistry at uni. However there isn't too much of Physics A level in chemistry. You'd get a brief introduction to some things which are vaguely relevant but there's nothing that you shouldn't be able to pick up easily at uni.