Which chemical equation represents a precipitation reaction? a. mg(clo3)2(aq) + 2hcl(aq) → mgcl2(aq) + 2hclo3(aq) b. albr3(aq) + 3lii(aq) → ali3(aq) + 3libr(aq) c. nh4no3(aq) + hbr(aq) → nh4br(aq) + hno3(aq) d. li2co3(aq) + fecl2(aq) → 2licl(aq) + feco3

Answer is D.

Among the given options, the products of equation A, B and C are aqueous solutions. Those are indicated by using (aq).

The balanced equation for the reaction between Li₂CO₃(aq) and FeCl₂(aq) is Li₂CO₃(aq) + FeCl₂(aq) → 2LiCl(aq) + FeCO₃(s)

LiCl is a salt while FeCO₃ is a Grey/green color precipitate. Hence, option D represents a precipitation reaction.

c. because step up transformer steps up the input voltage i.e increases the input voltage  

the number of turns are greater on the secondary side of step up transformer  

transformer does not handle dc current