Can someone please tell me the answer

52.068 amu

Explanation:

To calculate the average atomic mass of chromium, you have to first multiply the abundance of an isotope with its mass.

49.946 × 0.0435 = 2.173

51.941 × 0.838 = 43.527

52.941 × 0.0235 = 1.244

53.939 × 0.095 = 5.124

Next, add up all of the values, and you will get the average atomic mass.

2.173 + 45.527 + 1.244 + 5.124 = 52.068 amu

nacl is added to the aqueous of what? ? in order to get a proper answer you have to specify the exact composition of the aqueous solution.