Why is Jon Dalton’s discovery important to science? Help please

Dalton expressed his assumption in A Modern Model of Chemical Theory that atoms of various elements should be uniformly differentiated, based on their differing atomic weights. In doing so, he became the first scientist to explain atom behavior as regards weight measurement.

Explanation:

you need to take a look at the periodic system in order to sort these elements into pairs that would most likely exhibit similar chemical properties. first, you need to find elements that are found in the same group (groups are vertical in the periodic system), and then to see whether they have the same valence number. if they meet these criteria, they will have similar properties.

the first pair: ne (neon) and kr (krypton), are noble gases found in group 8

the second pair: li (lithium) and k (potassium), found in group 1

the third pair: s (sulfur) and te (tellurium), found in group 6

its first and third is your answer i did the qustion the fourth isnt right