Juan noticed that a door that sticks on hot days does not stick when it cools off at night. This is because the metal contracts as it cools. The reason for this is that, as the metal cools, the atoms: become smaller and take up less space .

slow down and move closer together.

merge together to form fewer atoms.

speed up and move further apart.

Write the symbol for every chemical element that has atomic number greater than 3 and atomic mass less than 12.0 u.

Imagine that a new planet is discovered with two moons of equal mass: moon a and moon b. the mass of the new planet is greater than the combined mass of its moons. moon a is farther away from the new planet than moon b. what is the planet's gravitational pull on moon a compared to the planet's gravitational pull on moon b? the planet's gravity repels moon a with a greater force than it repels moon b, which is why moon a is farther away. the gravitational pull on moon b is greater than on moon a because moon b is closer to the new planet than moon a. the gravitational pull on moon b is greater than on moon a because moon b is farther away from the new planet than moon a. the gravitational pull on moon a is the same as the gravitational pull on moon b because distance does not affect the planet's gravity.

Do polar molecules have ionic bonds?