Answer: A)
Explanation:
the deposition environment has changed from wind-dominated in the past to stream-dominated today.
Moles of P = 56,4g/30,974g/mole = 1,82 moles P
moles of O = 43,6/15,999 = 2,73 moles of O
converting to the simplest ratio:
For P : 1,82/1,82 = 1
For O : 2,73/1,82 = 1,5
1 P and 2 oxygens.
PO2 -> the empirical formula
hope this help
<span>The correct formula for Beryllium phosphate is Be3(PO4)2
Beryllium has a charge of +2 and phosphate has a charge of -3. So to make the charge equal to zero, 3x +2 = 6, and 2 x-3 = -6
-6 + +6 = 0</span>
<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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