Cryochemistry means using super-cold temperatures to study how chemicals react and change. It's like when you put things in the freezer to cool them down really quickly, but scientists use even colder temperatures.
When we freeze something, the molecules in the substance slow down and move less. Scientists use this to study how chemicals react because when they are frozen, they aren't moving around as much, so they are easier to study.
Scientists also use cryochemistry to study the things that happen when things get very cold, like how water turns into ice or how different chemicals interact with each other when they are frozen. They can learn a lot about how things work in nature by studying them at very cold temperatures.
Overall, cryochemistry helps scientists understand how chemicals behave and interact with each other, even at very low temperatures.