Answer:
![ppth=1.2ppth](https://img.qammunity.org/2021/formulas/chemistry/college/nqfwh1s3ubqyph88qgqlcrv9dl7f636zuo.png)
Step-by-step explanation:
Hello!
In this case, since the parts per thousand of a solute in a solute is defined in terms of its grams per kilogram of solution (unlike parts per million which are mg/kg) we can mathematically represent it via:
![ppth=\frac{grams_(solute)}{kg{solution}}](https://img.qammunity.org/2021/formulas/chemistry/college/o7edpya6eytgpl23b38cd4e2j4wmwj9h0y.png)
Now, since the whole human body acts as the solution and the chlorine in the form of ions as the solute, the required ppth turns out:
![ppth=(84.0g)/(70.0kg)\\\\ppth=1.2ppth](https://img.qammunity.org/2021/formulas/chemistry/college/3wlziuo7x0brdth2cvfogqkyymqcjyymcq.png)
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