The answer is D, medical diagnosis
Answer:
helium=1,2atm
argon=2,8atm
Explanation:
partial is pressure exerted by each gas in a system since 30% is helium it means 70% is argon
argon =70%x4
helium=30%4
The compound's molecular formula is C2H6. This is obtained by:
mass moles divided by smallest moles
C 32g 32/12 = 2.67 1
H 8g 8/1.01 = 7.92 approx. 3
Next, divide both terms by the smallest number of moles, 2.67. This gives 1 and 3. So the empirical formula is CH3 which has a molar mass of 15g/mol. Given the molar mass of the molecular formula as 30g/mole, we can calculate the factor by which to multiply the subscripts of CH3.
X = molar mass of molecular formula / molar mass of empirical formula = 30/15
X=2
So (CH3)2 is C2H6.
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
