Answer :
Final answer:
To find the number of milliequivalents of potassium in 780 mg, you convert the mass to grams, find the number of moles based on the molar mass of potassium, and then multiply by 1000 to get milliequivalents. The result is approximately 20 meq. The correct option is a) 20 meq
Explanation:
To determine how many milliequivalents (meq) are contained in 780 mg of potassium, you can use the following steps:
- First, convert the mass of potassium from milligrams to grams: 780 mg = 0.780 g.
- Next, calculate the number of moles of potassium. The molar mass of potassium (K) is approximately 39.10 g/mol. You can find the number of moles by dividing the mass of the potassium by its molar mass (0.780 g / 39.10 g/mol ≈ 0.01995 mol).
- Since potassium has a valence of 1, the number of moles is equivalent to the number of equivalents.
- Finally, to find the milliequivalents, multiply the number of equivalents by 1000 (because there are 1000 milliequivalents in one equivalent): 0.01995 mol × 1000 ≈ 19.95 meq
Therefore, the answer is approximately 20 meq, which is closest to option a) 20 meq.
