<span>3.5 moles CaCO3 (1 mole carbon/1 mole CaCO3) = 3.5 moles</span>
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!
It is B because horn coals are bigger and I read it in a book
Other natural material such as clay, wood, and stones can be changed into art.
Clay is pliable and is very easy to be molded into different shapes and sizes.
Wood can easily carved into different shapes, also different patterns can be easily etched on wood.
Stones of different variety and from different geological sources are painstakingly converted into statues or portraits of different life forms and scenery.