instruction:
Given a scientific passage and an answer, generate a question for the given answer.
question:
Passage: The heart is a muscular organ in the chest that consists mainly of cardiac muscle. It pumps blood through blood vessels by repeated, rhythmic contractions. Blood flows through four chambers of the heart when it beats. Heartbeat is controlled by electrical signals from special cells within the heart called the pacemaker. Answer: cardiac muscle
answer:
What type of muscle makes up most of the heart?

question:
Passage: Pressure is the result of force acting on a given area. It can be represented by the equation:. Answer: pressure
answer:
What property is the result of force acting on a given area?

question:
Passage: Gibbs free energy values can be used to determine equilibrium constants. Answer: equilibrium constants
answer:
Gibbs free energy values can be used to determine what?