Write balanced equations for each of the processes, choosing from the following substances as reactants: BaCl2 O2 H2SO4 HNO3 C2H5OH H2O Ca(OH)2 K Na2CrO4 KOH Pb(NO3)2

BaCl₂ and H₂SO₄

Explanation:

The reaction is the precipitation of BaSO₄ from solution.

This means that our reactants must contain the Ba ion and SO₄²⁻ ion.  The reactants that meet this criteria are the; BaCl₂ aand H₂SO₄

The reaction is given as;

BaCl₂ + H₂SO₄ --> BaSO₄ + 2HCl

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

it's c. elements are placed in rows based on how may valencies electrons have.