On a hot day , the sun causes the sidewalk to become very warm. how do the particles that make up the sidewalk change as the temperature increases?

a: they move closer together.
b: they move freely from place to place.
c: their kinetic energy decreases.
d: they move faster.

a graduated cylinder.

explanation:

"hydrogen bonding is the attraction of h atoms in the water molecule (slight + charge) to o atoms in a neighboring water molecule (slight - charge); it is a weak interatomic force. but it is still strong enough to the water molecules "stick" together."

in 1783 cavendish was working with his hydrogen gas and found that when he burned it and condensed the vapor it was water. this was very significant since it disproved the greek theory of elements completely since water was not a simple substance but the product of two gases. it was lavoisier who hearing of the experiment gave cavendish's gas the name hydrogen ("water-producer") and added that hydrogen burned by combining with oxygen and that water was a hydrogen-oxygen combination.

explanation: