a. What is the formula weight of magnesium iodide? (in amu) b. How many magnesiu
ID: 904135 • Letter: A
Question
a. What is the formula weight of magnesium iodide? (in amu)
b. How many magnesium ions are present in 2.86 x 10-4 mol of magnesium iodide? Enter your answer in scientific notation.
c. How many iodide ions are present in 2.86 x 10-4 mol of magnesium iodide? Enter your answer in scientific notation
d. How many magnesium ions are present in 97 mg of magnesium iodide? Enter your answer in scientific notation.
e. How many iodide ions are present in 97 mg of magnesium iodide? Enter your answer in scientific notation
Explanation / Answer
MgI2 --> 278.1139 amu
b)
MgI2
since 1 to 1 ratio (1 MG in 1 MgI2) then
M = 2.86*10^-4 mol of I-
# atoms --> 6.022*10^23 * 2.86*10^-4 = 1.72*10^20
c)
in the same sample, there is twice I ions per MG, therefore
2X1.72*10^20 = 3.44*10^20
d)
fin amount of ions in 97 mg of MgI2
mol = mass/MW = 0.097 g /278 = 3.489*10^-4 mol of MgI2
now change to molecules of MgI2 --> 6.022*10^23 * 3.489*10^-4 = 2.10*10^20 molecules of Mg
e)
Once again , in that sample there is twice molecules of I- than Mg, therefore
2*2.10*10^20 = 4.2 *10^20 molecules of I-
Related Questions
drjack9650@gmail.com
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.