Question

the chemical formula for potassium iodide is ki. a chemist determined by measurements that 0.0100 moles of potassium iodide participate in a chemical reaction. calculate the mass of potassium iodide that participates. round your answer to 3 significant digits.

Explanation:

Step1: Find molar mass of KI

Molar mass of K (potassium) is $39.10\ g/mol$, molar mass of I (iodine) is $126.90\ g/mol$. So molar mass of KI, $M = 39.10 + 126.90 = 166.0\ g/mol$.

Step2: Use mass = moles × molar mass

Given moles, $n = 0.0100\ mol$. Mass, $m = n\times M = 0.0100\ mol\times166.0\ g/mol$.

Step3: Calculate and round

$m = 0.0100\times166.0 = 1.66\ g$ (rounded to 3 significant digits).

Answer:

1.66