For which of the following activities might you want to hire a chemist?
Answer: D. testing a rock sample for gold content
Which of the following procedures involves a physical change in one of the substances?
Answer: C. separating a salt solution by evaporating the water
Answer:
0.85M
Explanation:
Given parameters:
Mass of CuCl₂ = 400g
Volume of water = 3.5L
Unknown:
Molarity of the solution = ?
Solution:
Molarity is one of the ways of expressing the concentrations of a solution. It is defined as the number of moles per unit volume of a solvent.
Molarity = 
To find the number of moles of CuCl₂;
Number of moles = 
Molar mass of CuCl₂ = 63.6 + 2(35.5) = 134.6g/mol
Number of moles =
= 2.97moles
Molarity =
= 0.85M