What is the molarity of ZnCl2(aq) that forms when 15.4 g of zinc completely reacts with CuCl2(aq) according to the following reaction? (Assume a final volume of 175 mL.)
Zn(s) + CuCl2(aq) --> ZnCl2(aq) + Cu(s)
I got the moles of Zn but don't know what to do with it
thanks
moles Zn = 15.4 g Zn/atomic mass Zn.
Convert moles Zn to moles ZnCl2 using the coefficients in the balance equation.
Then M ZnCl2 = moles ZnCl2/L soln.
Thanks!
To find the molarity of ZnCl2(aq) formed in the reaction, you need to use the following steps:
1. Calculate the moles of Zn in the reaction using its molar mass:
Moles of Zn = Mass of Zn / Molar mass of Zn
The molar mass of zinc, Zn, is approximately 65.38 g/mol. Therefore, you would divide the mass of Zn, 15.4g, by 65.38 g/mol to find the moles of Zn.
2. Use the stoichiometry of the balanced equation to determine the moles of ZnCl2 formed. From the balanced equation:
Zn(s) + CuCl2(aq) → ZnCl2(aq) + Cu(s)
The coefficient of ZnCl2 in the balanced equation is 1. This means that the number of moles of ZnCl2 formed is the same as the number of moles of Zn used in the reaction.
3. Calculate the volume of the solution using the given final volume of 175 mL. Convert the volume to liters:
Volume = 175 mL = 175 mL × (1 L/1000 mL)
4. Finally, calculate the molarity of ZnCl2 by dividing the moles of ZnCl2 by the volume of the solution in liters:
Molarity = Moles of ZnCl2 / Volume of solution (in liters)
Substitute the values you have calculated into the equation to find the molarity. Remember to round your final answer to the appropriate number of significant digits.
By following these steps, you should be able to determine the molarity of ZnCl2(aq) that forms when 15.4 g of zinc completely reacts with CuCl2(aq).