Question

If the water used in preparation of your zinc chloride solution in the volumetric flask contained some levels of Pb^2+ or Ca^2+ metal which is also known to chelate with EDTA. What will be the affect on the following? (Go over)

a.) number of moles EDTA calculated
b.) number of moles zinc calculated
c.) number of moles chloride calculated
d.) empirical formula that is the ratio zinc to chloride obtained

Answer 1

If the water used in the zinc chloride solution contains Pb^2+ or Ca^2+ metal, it will decrease the number of moles of EDTA calculated and the number of moles of chloride calculated. The number of moles of zinc calculated and the empirical formula of zinc chloride will remain the same.

Step-by-step explanation:

If the water used in preparation of your zinc chloride solution in the volumetric flask contained some levels of Pb^2+ or Ca^2+ metal which is also known to chelate with EDTA, it would have the following effects:

1. The number of moles EDTA calculated would decrease because EDTA would also chelate with Pb^2+ or Ca^2+ metal.
2. The number of moles zinc calculated would remain the same because zinc is not affected by the presence of Pb^2+ or Ca^2+ metal.
3. The number of moles chloride calculated would decrease because EDTA would also chelate with Pb^2+ or Ca^2+ metal, reducing the amount of chloride ions present.
4. The empirical formula that is the ratio of zinc to chloride obtained would remain the same because the presence of Pb^2+ or Ca^2+ metal does not change the ratio of zinc to chloride.