It seems you might be referring to a quick check or quiz regarding chemical reactions. Based on your responses, here are some possible interpretations or confirmations:
- 30 g - This could be indicating the mass of a reactant or product in a chemical reaction.
- They are rearranged - This likely refers to the fact that in a chemical reaction, atoms are rearranged to form new substances.
- Mass is conserved - This is a statement of the law of conservation of mass, which states that in a closed system, mass can neither be created nor destroyed during a chemical reaction.
- The atoms of the reactants are grouped during the reaction - This might refer to the fact that bonds break and new bonds form, causing atoms to regroup into different molecules.
- Four - This could indicate the number of atoms, molecules, formulas, products, or reactions being discussed.
If you have specific questions or need clarification on a particular topic related to chemical reactions, feel free to ask!