Answer:
In 4.5 grams of tetraphosphorus decoxide we have 3.85 * 10^22 phosphorus atoms
Explanation:
Step 1: Data given
tetraphosphorus decoxide = P4O10
Molar mass of P4O10 = 283.89 g/mol
Mass of P4O10 = 4.5 grams
Number of Avogadro = 6.022 * 10^23 / mol
Step 2: Calculate moles of P4O10
Moles P4O10 = mass P4O10 / molar mass P4O10
Moles P4O10 = 4.5 grams / 283.89 g/mol
Moles = 0.016 moles
Step 3: Calculate moles of P
For 1 mol P4O10 we have 4 moles of phosphorus
For 0.016 moles P4O10 we have 4*0.016 = 0.064 moles P
Step 4: Calculate number of P atoms
Number of P atoms = moles P * number of Avogadro
Number of P atoms = 0.064 moles * 6.022*10^23
Number of P atoms = 3.85 * 10^22 atoms
In 4.5 grams of tetraphosphorus decoxide we have 3.85 * 10^22 phosphorus atoms
Taking into account the scientific notation, the result of the sum is 10.84300×10³.
- <u><em>Scientific notation</em></u>
First, remember that scientific notation is a quick way to represent a number using powers of base ten.
The numbers are written as a product:
a×10ⁿ
where:
- a is a real number greater than or equal to 1 and less than 10, to which a decimal point is added after the first digit if it is a non-integer number.
- n is an integer, which is called an exponent or an order of magnitude. Represents the number of times the comma is shifted. It is always an integer, positive if it is shifted to the left, negative if it is shifted to the right.
-
<u><em>Sum in scientific notation</em></u>
You want to add two numbers in scientific notation. It should be noted that when the numbers to be added do not have the same base 10 exponent, the base 10 power with the highest exponent must be found. In this case, the highest exponent is 3.
Then all the values are expressed as a function of the base 10 exponent with the highest exponent. In this case: 9.7300×10²= 0.97300×10³
Taking the quantities to the same exponent, all you have to do is add what was previously called the number "a". In this case:
0.97300×10³ + 9.8700×10³= (0.97300+ 9.8700)×10³= 10.84300×10³
Finally, the result of the sum is 10.84300×10³.
Learn more:
Final volume is 400 mL
<span>The moles in MgSO4 is 0.00788 </span><span>mL
</span>
The new concentration is 0.197
<span>the theoretical yield which is the expected yield and the actual yield obtained are not always the same. therefore percent yield is calculated which shows how much of the percentage of the theoretical yield is actually obtained.
the theoretical yield = 56.0 g
actual yield = 47.0 g
percent yield = actual yield / theoretical yield x 100 %
percent yield = 47.0 / 56.0 x 100% = 83.9 %
percent yield = 83.9 %</span>
