Question 18

1800 mg of sodium chloride is in 200 mL of normal saline (NS).

Normal saline (NS) is defined as a solution of 0.9% sodium chloride, which translates to 9 grams of sodium chloride per liter. Therefore, in 200 mL, which is one-fifth of a liter, there would be 1.8 grams or 1800 mg of sodium chloride.

A) 550

This option is incorrect as it underestimates the amount of sodium chloride in 200 mL of normal saline. A 0.9% solution contains much more sodium chloride than 550 mg, making this choice inaccurate.

B) 1800

This option is correct because it accurately reflects the amount of sodium chloride in a 200 mL solution of normal saline. Since normal saline contains 9 grams of sodium chloride per liter, in 200 mL, the sodium chloride content is 1.8 grams or 1800 mg.

C) 3600

This choice is incorrect because it overestimates the sodium chloride content in 200 mL of normal saline. The calculation shows that only 1800 mg is present, thus making 3600 mg an inaccurate figure.

D) 5500

This option is also incorrect as it substantially exceeds the actual sodium chloride content in 200 mL of normal saline. The correct amount of sodium chloride is 1800 mg, making this choice inaccurate.

Conclusion

The correct answer, 1800 mg, is derived from the established concentration of sodium chloride in normal saline. Other options do not align with this concentration, highlighting the importance of understanding solution concentrations in clinical settings. Therefore, option B is definitively the correct choice.