Can someone check my answer?

Which of the following are chemical reactions?
(the one is a star is my answers, you can have more than one.)
1. mixing oil and vinegar to make salad dressing
2. Making caramel sauce*
3. Pour chocolate sauce into milk to make chocolate milk.
4. Getting a suntan*

Question

Can someone check my answer? 

Which of the following are chemical reactions?
(the one is a star is my answers, you can have more than one.) 
1. mixing oil and vinegar to make salad dressing
2. Making caramel sauce*
3. Pour chocolate sauce into milk to make chocolate milk. 
4. Getting a suntan*

anonymous · Answer

Making caramel sauce (you're adding heat and changing chemical compounds), and also suntan, pigments in skin + UV is not reversible. so 2 & 4 both chemical

anonymous · Answer

Yes, the mixing is not a reaction unless new chemical molecules are formed, rather than having the original ones just divided more finely ans spread around.