An unknown substance kept in a sealed container at stp had a density of 808 kg/m3. when the container was opened and the substance was exposed to room temperature, its density became 1.25 kg/m3. which change did the substance most likely undergo?
gas to solid
liquid to solid
gas to liquid
liquid to gas
im not sure on this one but i think its the last one
answer & explanation:
subatomic particles are particles much smaller than atoms.
atoms are composed mainly of protons, neutrons, and electrons.
³²p:number of electrons: 15,number of protons: 15,number of neutrons: 17.
³¹p:number of electrons: 15,number of protons: 15,number of neutrons: 16.
your answer should be d. about 4 years. hope this ! =^-^=
(the light reflected from the surface of the moon takes only a second to reach earth. the sun is more than 8 light-minutes away. and so, if the light from the nearest star (alpha centauri) takes more than 4 years to reach us, we're seeing that star 4 years in the past.) quora.com