The catch is that the audio CD is uncompressed. While you might have been able to put seven or eight hours of MP3s onto a single data CD before, youâre out of luck with an audio CD. These contain only about 70 minutes or so. It may take several audio CDs to hold what you might currently have on a single data CD.
Example 1: mass percent = (mass of chemical/total mass of compound) x 100 = (5 g/105 g) x 100. Example 2: We want to rearrange the mass percent equation to solve for the unknown mass of the chemical: mass of the chemical = (mass percent*total mass of the compound)/100 = (15*175)/100. 5. Calculate the mass percent.
The atomic weight of an element depends on the abundance of its isotopes. If you know the mass of the isotopes and the fractional abundance of the isotopes, you can calculate the element's atomic weight. The atomic weight is calculated by adding the mass of each isotope multiplied by its fractional abundance. For example, for an element with 2 isotopes: atomic weight = mass a x fract a + mass b x fract b. If there were three isotopes, you would add a 'c' entry. If there were four isotopes, you'd add a 'd', etc.