Students explore the concept that chemical reactions involve the breaking of bonds between atoms in the reactants, and the rearrangement and rebonding of these atoms to make the products. Students ...

Chemical reactions make new chemicals. Atoms are rearranged during a chemical reaction, but the number of atoms does not change. A catalyst is a substance that speeds up a chemical reaction.

Physical chemists are focused on understanding the physical properties of atoms and molecules, the way chemical reactions work, and what these properties reveal. Their discoveries are based on ...

Chemical equations model the changes that happen in chemical reactions. The mole and Avogadro's constant - OCR Gateway What is the mole and Avogadro's constant? The mole is the unit for amount of ...