Answer:
0.020 mol
Explanation:
Let's consider the following relations:
- 20 drops of a liquid have a volume of 1 mL.
- The density of the solution is 1.685 g/mL, that is, each milliliter of solution has a mass of 1.685 g of solution.
- There are 85 g of phosphoric acid per 100 grams of solution (85 % by weight).
- The molar mass of phosphoric acid is 97.99 g/mol
With these relations, we can calculate the moles of phosphoric acid in 27 drops of solution.
Exact numbers need not be measured. They can be counted. Conversion factors and countable units come under exact numbers. Measured quantities are measured using a device.
1) Number of microseconds in a week -Exact as it need not be measured. It can be estimated using the conversion factors between microseconds, seconds, minutes, hours, days and week.
2) Number of inches in a mile - Exact number as it is an established conversion factor.
3) The mass of a paper clip - Measured number as it has to measured using a weighing balance.
4) The number of pages in a book - Exact number as it is not measured. It can be counted.
5) Surface area of the dime-Measured number as it has to be measured.
6) The number of ounces in a pound-Exact number as it is a constant value.
The mass of the air sample is calculated using the below
Q(heat)=M(mass) x C(specific heat capacity) x delta T(change in temperature)
Q= 120.j
M=?
C= 1.0j/g/c
delta T =45.0-33.2=11.8 c
by making M the subject of the formula
M=Q/C delta T
= 120 j/ 1.0 j/g/c x11.8 c=10.17 grams
L = an integer from 0 to n-1
<span>mL = an integer from -L to +L </span>
<span>ms = + or - 1/2 </span>
<span>the format is (n, L, mL, ms) </span>
<span>so your </span>
<span>n = 3... this is OK </span>
<span>L = 2.. also OK.. if n=3, L can = 0, 1, or 2 </span>
<span>mL = -3 is NOT ok... if L=2.. mL can only be -2, -1, 0, +1, or +2 </span>
<span>ms = +1/2 and that is ok
Hope this helps!</span>
