Using the activity series, the reaction 2Al+6HBr-2 AlBr3+3 H2 will only occur ifAl is above Be on the periodic table or heat is added to the reaction or a precipitate forms or Al is above H on the activity series

Al is above H on the activity series

Explanation:

The given chemical reaction is expressed as:

            2Al + 6HBr →  2AlBr₃ +  3H₂

The reaction above is a single displacement or replacement reaction and will only occur if Al is above H on the activity series.

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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