Can anyone help me plz on my chemistry test fast its on percentage yield ill mark brainliest for correct answer.

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

c is the answer because when something is left after something evaporates that shows the chemical change.

indium, and thallium have three electrons i think

it's c (engineer's do their work with mechanical stuff not on any living being)