Question

A tube of toothpaste contains 0.76 g of sodium monofluorophosphate (Na2PO3F) in 100 mL. What is the concentration of Na2PO3F in the toothpaste?

a) 0.76 g/mL
b) 0.76 g/L
c) 0.38 g/mL
d) 0.38 g/L

Answer 1

The concentration of sodium monofluorophosphate (Na2PO3F) in the toothpaste is 7.6 g/L, which is not one of the provided options. The mass is divided by the volume after conversion to liters to yield the correct concentration in g/L.

Step-by-step explanation:

The question is asking to find the concentration of sodium monofluorophosphate (Na2PO3F) in toothpaste, given that there are 0.76 g of Na2PO3F in 100 mL of toothpaste. To calculate the concentration, we need to divide the mass of Na2PO3F by the volume of the toothpaste (assuming the density of the toothpaste is such that 100 mL has a negligible mass compared to the mass of Na2PO3F).

To convert to the correct units for concentration, which is grams per liter (g/L), first we should convert the volume from milliliters to liters:

100 mL = 0.1 L

Now, the concentration can be calculated as follows:

Concentration = mass/volume

Concentration = 0.76 g / 0.1 L

Concentration = 7.6 g/L

Thus, none of the provided options (a) 0.76 g/mL, (b) 0.76 g/L, (c) 0.38 g/mL, or (d) 0.38 g/L are correct. The correct concentration should be 7.6 g/L.