The comet cools down and begins to glow brightly as a result of this decreased temperature.

True or False?

Describe an experiment that could further explore physical or chemical change.

Indicate whether each source is reliable or unreliable a goverment website a university professor's personal blog a commercial website an online peer-reviewed science journal

Why does an apple look red to us?

Calculate the average atomic mass of chromium

A student states that 203.9 g of table sugar will form a saturated solution in 100 g of water. What do you need to know to decide whether this statement is correct?

Which of the following is a measure of randomness in a system? A) entropy. B) kinetic energy. C) potential energy. D) chemical energy.

What substance can be broken down by chemical means? A) ammonia B) aluminum C) antimony D) argon (Castle learning question)

How the law of conservation of mass could be useful for investigating chemical changes

A covalent chemical bond is one in which outer-shell electrons of two atoms are shared so as to satisfactorily fill the outer electron shells of both atoms. protons and neutrons are shared by two atoms so as to satisfy the requirements of both atoms.

To break a chemical bond, energy must be (1) absorbed (2) destroyed (3) produced (4) released