Fill in the blank. A pure substance has a/an composition.
A/An is composed of two or more types of matter that can be present in varying amounts.
A solution is a/an mixture.
A mixture that is not uniform throughout is a/an mixture.
A pure substance that cannot be broken down chemically is a/an .
A characteristic of matter that’s not associated with a change in its chemical composition is known as a/an property.
Wax melting is an example of a/an change in the state of matter.
A banana peel turning brown is an example of a/an change in the state of matter.

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