Physical, because the ice is only changing it's state. It's not changing to a new substance.
Slow chemical change
It is a chemical change because the erosion is due to the chemical reaction between the acid and the in the rain and the calcium carbonate.
It is slow due to the concentration of acid is low.
Answer:
left to right across a period when it decreases and when it increases top to bottom in a group,
hope i helped
J.J. Thomson hypothesized and discovered that the atom was not the smallest unit of matter but that instead there were much smaller units. He discovered "sub-atomic particles" which make up atoms. The sub-atomic particle that Thomson discovered was the electron. He discovered this through a process of experiments testing cathode rays.
In every reaction, mass cannot be destroyed nor created as defined by the law of conservation of mass. Energy also cannot be destroyed when a chemical reaction takes place