A 125g sample of a radioisotope with a half life of 25 years is found in a basement after being misplaced for 75 years. What was the mass of the original sample?

Two solutions of the same uv-absorbing molecule were analyzed by uv-vis spectroscopy on the same instrument using 1 cm pathlength cells. use data from the table to calculate by what percentage the concentration of solution b is compared to that of solution a. sample absorbance at 315nm a 0.45 b 0.80

Imagine that the rightward current flows in the rod for a short time. as a result, what will the net charge on the right and left ends of the rod become? left end negative and right end positive left end negative and right end negative left end negative and right end nearly neutral left end nearly neutral and right end positive both ends nearly neutral

Awaiver with a period of 0.008 second has a frequency of a. 800hz. b. 80hz. c. 125hz. d. 12.5hz.