A 500g toothpaste sample has 0.2g fluoride concentration. What is the concentration of fluoride in terms of ppm level?
Correct answer: C. 400
- A. 250
- B. 200
- C. 400
- D. 1000
Explanation
The concentration of fluoride in terms of ppm (parts per million) can be calculated as follows: 1 ppm = 1 mg of solute per 1 liter of solution Since the mass of the toothpaste sample is 500g and the concentration of fluoride is 0.2g, we can convert the concentration to mg/g: 0.2 g = 200 mg To calculate the ppm level, we need to divide the mass of fluoride by the total mass of the toothpaste and then multiply by 1 million: 200 mg / 500 g x 1,000,000 = 400 ppm Therefore, the concentration of fluoride in the toothpaste sample is 400 ppm
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