<span>To find the molar mass, look at a periodic table for each element.
Ibuprofen, C13 H18 and O2. Carbon has a molar mass of 12.01 g, Hydrogen has 1.008 g per mole, and Oxygen is 16.00 g per mole.
C: 13 * 12.01
H: 18 * 1.008
O: 2 * 16.00
Calculate that, add them all together, and that is the molar mass of C13H18O2.
Molar mass: 206.274
Next, you have 200mg in each tablet, with a ratio of C13H18O2 (molar mass) in GRAMS per Mole
So, you need to convert miligrams into grams, which is 200 divided by 1000.
0.2 g / Unknown mole = 206.274 g / 1 Mole
This is a cross multiplying ratio where you're going to solve for the unknown moles of grams per tablet compared to the moles per ibuprofen.
So, it's set up as:
0.2 g * 1 mole = 206.274 * x
0.2 = 206.274x
divide each side by 206.274 to get X alone
X = 0.00097
or 9.7 * 10^-4 moles
The last problem should be easy to figure out now that you have the numbers. 1 dose is 2 tablets, which is the moles we just calculated above, times four for the dosage.
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•3.9g of ammonia
•molar mass of ammonia = 17.03g/mol
1st you have to covert grams to moles by dividing the mass of ammonia with the molar mass:
(3.9 g)/ (17.03g/mol) = 0.22900763mols
Then convert the moles to molecules by multiplying it with Avogadro’s number:
Avogadro’s number: 6.022 x 10^23
0.22900763mols x (6.022 x 10^23 molecs/mol)
= 1.38 x 10^23 molecules
Solve these problems like weighted averages:
The first one:
Multiply the masses (isotope numbers) by the decimal form of the percentage. Add them
0.076 (6) + 0.924 (7) = 6.924
The second one:
0.2 (10) + 0.8 (11) = 10.8
If you think about it, these answers make sense. 6.924 is much closer to 7 than to 6 (since there's a lot more lithium-7 than there is lithium-6). 10.8 is closer to 11 than to 10.
Answer:
The answer is letter A. Diamond
Explanation:
The diamond is a crystalline form of carbon, with a cubic structure, of the sp³ type, that is, each carbon atom of the structure is linked to four other carbon atoms, forming a tetrahedral geometry.
Answer:
0.55 atm
Explanation:
First of all, we need to calculate the number of moles corresponding to 1.00 g of carbon dioxide. This is given by
where
m = 1.00 g is the mass of the gas
Mm = 44.0 g/mol is the molar mass of the gas
Substituting,
Now we can find the pressure of the gas by using the ideal gas law:
where
p is the gas pressure
V = 1.00 L is the volume
n = 0.0227 mol is the number of moles
R = 0.082 L/(atm K mol) is the gas constant
T = 25.0 C + 273 = 298 K is the temperature of the gas
Solving the formula for p, we find
