What percentage of the total atomic mass of magnesium bromide (MgBr_(2)) is composed of bromine'? Hint - consider the mass of both atoms of bromine in your calculation. 87% 13% 43% 63%

To find the percentage of the total atomic mass of magnesium bromide (MgBr2) that is composed of bromine, we need to calculate the atomic mass of bromine in MgBr2 and then divide it by the total atomic mass of MgBr2.<br /><br />Step 1: Calculate the atomic mass of bromine in MgBr2.<br />The atomic mass of bromine (Br) is approximately 79.9 amu. Since there are two bromine atoms in MgBr2, the total atomic mass of bromine is:<br />2 * 79.9 amu = 159.8 amu<br /><br />Step 2: Calculate the total atomic mass of MgBr2.<br />The atomic mass of magnesium (Mg) is approximately 24.3 amu. Adding the atomic mass of bromine, the total atomic mass of MgBr2 is:<br />24.3 amu + 159.8 amu = 184.1 amu<br /><br />Step 3: Calculate the percentage of the total atomic mass of MgBr2 that is composed of bromine.<br />Percentage = (Atomic mass of bromine / Total atomic mass of MgBr2) * 100<br />Percentage = (159.8 amu / 184.1 amu) * 100<br />Percentage ≈ 86.7%<br /><br />Therefore, the percentage of the total atomic mass of magnesium bromide (MgBr2) that is composed of bromine is approximately 86.7%.