A reacting mixture draws heat from nearby water. Which label fits this process?

As wood burns, in which direction does heat move overall?

What must happen for a chemical bond to be broken?

What happens when atoms form a chemical bond?

During a reaction, making new bonds gives off more energy than separating the original bonds uses. What happens nearby?

How should the reaction shown in this profile be classified?

According to the profile, what is the net energy transfer for the forward reaction?

Two identical cups contain equal volumes of water at the same starting temperature. Epsom salt is added to only one. Why record temperatures in both cups?

Liza records 28 °C before adding Epsom salt to water. What temperature change does the thermometer show afterward?

In the steel wool activity, which gas is responsible for rust formation?

A thermometer in moist steel wool initially reads 25 °C. The wool is left in air at 25 °C without external heating. What does the later reading indicate about rusting?

For dough inside an oven, how is the overall baking process classified?

When liquid water becomes ice, what happens thermally?

Which example involves heat uptake without forming a new substance?

Why can wet clothes feel cool as they dry?

What supplies the energy that plants use to make glucose during photosynthesis?

Which statement describes energy transfer during cellular respiration?

The Haber-Bosch process combines nitrogen and hydrogen to make ammonia. How is this reaction classified?

In ammonia synthesis for fertilizers (N₂ + 3H₂ → 2NH₃), breaking the reactant bonds takes in about 2,253 kJ and forming the product bonds gives out about 2,346 kJ. What is the net energy change?

Two pots each transfer 100 kJ to pasta. An uncovered pot loses 40 kJ to the room; a covered pot loses 15 kJ. How much less energy must the stove supply to the covered pot?