Is sublimation a chemical change?
No. It is a physical change. See explanation.
A chemical change (reaction) is a process where one or more substances react to create other substances. Example:
In this reaction from 2 substances (acid and a hydroxide) other 2 substances (salt and water) are created.
If a substance (for example water) sublimates NO new substances are formed. Only the state of matter changes. A solid (ice) becomes a gas (vapour) but it is still the same chemical substance - water (