Unit 3 4, if we are to minimize the total number of chloride ions impacting the environment upon ap- plication of road salt in the winter, which would be better to use on the roadss. a 23 w/w% sodium chloride solution or a 23 w/w% calcium chloride solution? show calculations to explain your choice! trying

It would be better to use the NaCl solution.

Explanation:

We can calculate the amount of Cl⁻ in each salt.

NaCl

Taking into account the molar masses, there are 35.5 g of Cl⁻ every 58.5g of NaCl. So, for a 23 w/w% solution of NaCl:

CaCl₂

Taking into account the molar masses, there are 71.0 g of Cl⁻ every 111g of CaCl₂. So, for a 23 w/w% solution of CaCl₂:

The concentration of Cl⁻ in the NaCl solution is 14.0 w/w% and its concentration in the CaCl₂ solution is 14.7 w/w%, so we would choose the NaCl solution to minimize Cl⁻ concentration.

answer: c. the experiment shows that the red substance experienced a chemical change.

explanation: chemical change is the change in which chemical composition of the substance changes. physical change is the change in which there is no change in chemical composition.

chemical changes are accompanied by following changes:

a) precipitate formation

b) energy is released or absorbed

c) formation of bubbles

d) change in color

as it is given that the red color has disappeared and there is production of gas, it means the red substance has undergone a chemical change.

e