No absolutely not - chalky soil is the one they won't do well in. In a pot, the best compost is John Innes No 2 or 3, mixed with some ericaceous compost. They like, rich, moist but free draining soil.

Hi Dorsetgirl and welcome to GoY. How big is your 'large pot'? This is a tree that will, eventually grow to up to 4 metres in height and spread and really needs to be in the ground.

Grow in moist, humus-rich, well-drained neutral to acid soil in sun or partial shade with shelter from cold winds. Or, in other words, no do not add chalk or lime.

I have Magnolia Susan which has been growing in my garden which has alkaline soil for the last 8 years. It has no problems and is in full flower at the moment, so I can't agree with Bamboo's comment that they won't do well in chalky soil, but if you are going to try and grow it in a pot then best to follow Bamboo's advice.

I planted M.Susan in a pot last year. Pot is about 2ft high x 15-18inch diameter. I used general purpose compost mixed with well-rotted manure.
The nursery label states "well-drained soil.... Mix an organic soil improver and general fertiliser with the infill soil." Susan will be fairly happy in neutral soil, prefers acidic and may (just) tolerate a slightly alkali soil as long as she has a rhodedendron feed once or twice a year.

She's one of the small magnolias, I double checked on the height when I bought mine and was advised that she could be kept to required height by light pruning.