Which solution of CuCl₂ will lead to the fastest reaction with aluminum?*10g CuCl₂ in 100mL5g CuCl₂ in 50mL5g CuCl₂ in 100mL10g CuCl₂ in 50mL

The speed of a chemical reaction often depends on the concentration of the reactants. The higher the concentration, the faster the reaction usually is.

Concentration is calculated by dividing the mass of the solute (in this case, CuCl₂) by the volume of the solution. Here are the concentrations for each solution:

1. 10g CuCl₂ in 100mL = 10g/100mL = 0.1g/mL
2. 5g CuCl₂ in 50mL = 5g/50mL = 0.1g/mL
3. 5g CuCl₂ in 100mL = 5g/100mL = 0.05g/mL
4. 10g CuCl₂ in 50mL = 10g/50mL = 0.2g/mL

So, the solution with the highest concentration of CuCl₂, and therefore the one that will lead to the fastest reaction with aluminum, is the 10g CuCl₂ in 50mL solution.