Scientists have known the consequences of mixing sodium bicarbonate and vitamin C ever since 1936, when a study on the subject was published in the "Journal of Nutrition." The authors of this study measured the amount of vitamin C recovered from the urine of people who drank a fixed amount of orange juice. The authors determined that the amount of vitamin C excreted was decreased by administration of sodium bicarbonate. Followup studies in the 1940s showed that this effect was due to the neutralization of the vitamin C by the sodium bicarbonate.
Independent variable would be salt since you can't change it in this experiment.
40. Because sodium chloride is NaCl
The answer is: b)16,200 seconds :)
Most ions tend to be D. Salts. Hope this helps!