Across
- 2. When a chemical reaction occurs, old bonds b______ and new bonds are made.
- 4. During an endothermic reaction, energy is taken i___ from the surroundings.
- 6. Every chemical reaction starts off with r_________ that make products.
- 8. In a molecule of hydrogen (H2), there are two hydrogen atoms. There is a chemical b_______ holding the two atoms together.
Down
- 1. Every chemical reaction ends up with p___________ that are made from the reactants.
- 3. In every chemical reaction, e_________ is either taken in or given out to the surroundings.
- 5. When we mix two chemicals together, we say a chemical r________ has occurred.
- 7. The symbol for oxygen is O2. We say that oxygen has two a________ of oxygen.