Question

question 2
chemical equations ____.
describe only biological changes
describe chemical reactions
give directions for naming chemical compounds
show how to write chemical formulas

question 3
what does the symbol δ in a chemical equation mean?
heat is supplied to the reaction.
precipitate
yields
a catalyst is needed.

Explanation:

Chemical equations represent chemical reactions, showing the reactants and products and their relative amounts. The symbol $\Delta$ in a chemical equation indicates that heat is supplied to the reaction.

Answer:

Question 2: describe chemical reactions
Question 3: Heat is supplied to the reaction.