C. Ne
down here is the list of monoatomic elements, just for you :)
Answer:
An atom is the basic building block of matter. Anything that has a mass-- in other words, anything that occupies space--is composed of atoms.
Answer:
Temperature and Pressure
Explanation:
Temperature and pressure cause change in volume.
So any change in volume will alter the ratio of density as given by equation of density.
Density = mass/ volume
Change in volume will alter the ratio.
Kindly mark it branliest if the answer is little bit satisfying.
Let's eliminate these one by one.
The first pair would not be the same, as X would most likely be in group IA, and Y would be in group VIIA, because of their tendency to gain and lose electrons.
The second pair would also violate the same rule, but X would most likely be in group IIA, and Y would most likely be in group VIA.
The third pair would not be the same, as X is most likely in group VIIA, and since Y has eight valence electrons, it is most likely a noble gas.
The final pair has X with atomic number 15, making it phosphorous. Phosphorous wants to gain 3 electrons to have a full octet of 8 outer "valence" electrons, and Y would also like to gain 3 electrons. This means it is possible that the final pair would be in the same group.