Answer;
=28.09 amu
Explanation;
In this problem, they did not give us the percentages. However, since we know the number of atoms, we can easily calculate the percentages. For example:
(460 X 100)/500 = 92%
If we do this for all three isotopes,
(460 × 25)/500 = 5 %
(460 × 15) /500 = 3%
-We get 92%, 5%, and 3%. (We'll assume these are absolute numbers for determining our significant figures).
Now the problem is just like the previous one. First convert the percentages into decimals. Then multiply those decimals by the masses and add. Here's the solution:
= (0.92) X (27.98 amu) + (0.05) X (28.98 amu) + (0.03) X (29.97 amu)
= 25.74 amu + 1.449 amu + 0.8991 amu
= 28.09 amu
?
.........................
Answer: -
A) 3.59
Explanation: -
The number of significant figures in 2.06 = 3
The number of significant figures in 1.743 = 4
The number of significant figures in 1.00 = 3
During multiplication of significant figures, the number of significant figures in the answer would be the smallest value that is 3 in this case.
2.06 x 1.743 x 1.00 = 3.5908.
The answer to 3 significant figures is
2.06 x 1.743 x 1.00 = 3.59
Thus, Andi when performs the calculation that is shown below.
(2.06)(1.743)(1.00)
the answer be reported using the correct number of significant figures as A) 3.59