A 170 g sample of an aqueous alcohol solution contains 20.0% alcohol by
mass. What is the mass of solvent present in the solution?
20 g
34g
136 g
170 g

We are given that alcohol is the solute, which leaves whatever is not alcohol as the solvent. 20.0% of the solution’s mass is alcohol, meaning 80.0% of the solutions mass is solvent. We are given its mass as 170 g, so just multiply 0.800*170 g = 136 g.

The activity series is shown in the attached picture. if the element is below the other, then you can displace the other. following the activity series as a guide, the reactions are as follows: nickel and aluminum chloride3 ni + 2 alcl₃  → 3 nicl₂ + 2 albarium and copper bromideba + cubr  →  no reaction because cu is less oxidizable than bapotassium nitrate and aluminum3 kno₃ + al  → al(no₃)₃ + 3 ksodium phosphate and zincnaso₄ + zn  → znso₄ + na

Idon't know hope someone you