model 2 - natural abundance information for magnesium\nperiod: \n| isotope | natural abundance on earth (%)…
model 2 - natural abundance information for magnesium\nperiod: \n| isotope | natural abundance on earth (%) | atomic mass (amu) |\n| ---- | ---- | ---- |\n| $^{24}$mg | 78.99 | 23.9850 |\n| $^{25}$mg | 10.00 | 24.9858 |\n| $^{26}$mg | 11.01 | 25.9826 |\n7. consider the natural abundance information given in model 2.\n a. calculate the expected number of atoms of each isotope that will be found in a sample of 20 atoms of mg. hint: the number of atoms must be a whole number!\n b. is model 1 accurate in its representation of magnesium at the atomic level? explain.\n8. if you could pick up a single atom of magnesium and put it on a balance, the mass of that atom would most likely be ____ amu. explain your reasoning.\n9. refer to a periodic table and find the box for magnesium.\n a. write down the decimal number shown in that box.\n b. does the decimal number shown on the periodic table for magnesium match any of the atomic masses listed in model 2?\n10. the periodic table does not show the atomic mass of every isotope for an element.\n a. explain why this would be an impractical goal for the periodic table.\n b. is it important to the average scientist to have information about a particular isotope of an element? explain.
Answer
7a
Explanation:
Step1: Calculate for $^{24}Mg$
Multiply abundance by total atoms. $20\times\frac{78.99}{100}=15.798\approx16$
Step2: Calculate for $^{25}Mg$
Multiply abundance by total atoms. $20\times\frac{10.00}{100}=2$
Step3: Calculate for $^{26}Mg$
Multiply abundance by total atoms. $20\times\frac{11.01}{100}=2.202\approx2$
Answer:
$^{24}Mg$: 16 atoms, $^{25}Mg$: 2 atoms, $^{26}Mg$: 2 atoms
7b
Brief Explanations:
Without information about Model 1, we cannot determine accuracy. Need details on its representation of magnesium at atomic - level to compare with natural - abundance data in Model 2.
Answer:
Cannot be determined without information about Model 1
8
Brief Explanations:
Since $^{24}Mg$ has the highest natural abundance (78.99%), a randomly - selected single atom of magnesium is most likely to be $^{24}Mg$ with atomic mass 23.9850 amu.
Answer:
23.9850 amu, because $^{24}Mg$ has the highest natural abundance
9a
Brief Explanations:
Look up magnesium in periodic table. Its atomic mass (average atomic mass) is approximately 24.305.
Answer:
24.305
9b
Brief Explanations:
The atomic masses in Model 2 are for individual isotopes. The number in periodic table is average atomic mass. So, it does not match any of them.
Answer:
No
10a
Brief Explanations:
There are many isotopes for some elements. Listing all their atomic masses would make the periodic table overly complex and cluttered, and average atomic mass is more useful for general chemical calculations.
Answer:
It would make the periodic table overly complex and cluttered, and average atomic mass is more useful
10b
Brief Explanations:
Yes, in some cases like nuclear chemistry, radiochemistry, and understanding radioactive decay or isotope - specific reactions, information about a particular isotope is crucial.
Answer:
Yes, especially in nuclear and radiochemistry related studies