Answer:
A
Explanation:
because number of particle = moles × 6.02 × 10^23
which gives the answer as an A
Physical changes happen when you do/mix something that can be reversed. Best example is ripping a paper, you can just tape it back together so it is just an observable thing that changes, which is a physical change. Chemical changes happen when you mix things and they make a new substance and can’t be reversed. The best example of this is the Statue of Liberty, which changed in color due to the chemical change between the oxygen and copper, which created a new substance (rust) which made it green instead of copper.
Sorry for the long answer but hope this helps!
Answer:
B
Explanation:
It's the same substance but in different states.
HETEROGENEOUS mixtures contain substances that are
not uniform in composition. The parts in the mixture can be separated by physical means.
Reptiles arose during the Carboniferous period. Therefore making the answer Reptiles