Percent yield or yield is mathematically defined as:
Yield = Actual amount / Theoretical amount
So to solve the yield, let us first calculate the
theoretical amount of POCl3 produced. The balanced chemical reaction for this
is:
6 PCl5 + P4O10 ---> 10 POCl3
Since P4O10 is stated to be supplied in large amount, then
PCl5 becomes the limiting reactant.
So we calculate for POCl3 based on PCl5. To do this let us
convert the amount into moles: (molar mass PCl5 = 208.24 g/mol)
n PCl5 = 42.66
grams / (208.24 g/mol)
n PCl5 = 0.205 mol
Now based on the
stoichiometric ratio of the reaction:
<span>n POCl3 = 0.205 mol (10
POCl3 / 6 PCl5)
n POCl3 = 0.3414 mol POCl3</span>
Converting to mass (molar
mass POCl3 = 153.33 g/mol)
m POCl3 = 0.3414 mol (153.33 g/mol)
m POCl3 = 52.35 g
Calculating for yield:
Yield = 47.22 g/ 52.35 g
Yield = 0.902
<span>%Yield = 90.2 % (ANSWER)</span>
Answer:
c. 2.16 × 10^8 kJ
Explanation:
In the given question, 2 C-12 nuclei were used for the reaction and the mass of C-12 is 12.0000 amu. Therefore, for 2 C-12 nuclei, the mass is 2*12.0000 = 24.0000 amu.
In addition, a Na-23 and a H-1 were formed in the process. The combined mass of the products is 22.989767+1.007825 = 23.997592 amu
The mass of the reactant is different from the mass of the products. The difference = 24.0000 amu - 23.997592 amu = 0.002408 amu.
Theoretically, 1 amu = 1.66054*10^-27 kg
Thus, 0.002408 amu = 0.002408*1.66054*10^-27 kg = 3.99858*10^-30 kg
This mass difference is converted to energy and its value can be calculated using:
E = mc^2 = 3.99858*10^-30 *(299792458)^2 = 3.59374*10^-13 J
Furthermore, 1 mole of hydrogen nuclei contains 6.022*10^23 particles. Thus, we have:
E = 3.59374*10^-13 * 6.022*10^23 = 2.164*10^11 J = 2.164*10^8 kJ
Option B: 4.3
There are following rules for rounding off numbers:
1. If the rounding digit has digit less than 5 (1,2,3 and 4) to its right, all the digits on right side of the rounding digit will drop out.
2. If the rounding digit has digit equal and greater than 5 (5,6,7,8 and 9) to its right, one is added to the rounding digit.
Jeff has to weigh 4.312 g sample of NaCl. To round off the underline number 4.<u>3</u>12, check for the digit right to it. It has 1, which is less than 5 thus according to the Rule 1, all the digits on right side of the rounding digit will drop out and the number gets rounded off to 4.3.
Therefore, 4.3 is most accurate measurement by Jeff.
Answer: All organic compound depends on H-bonding with water. more stronger H-bonding with water more will be soluble.
Explanation:
1. It depends primarily upon the function groups of that compound. It also depends on the size of the compound.
2. some organic compound which soluble in water for example: alcohols, ethers, carboxylic acids. Because of the functional groups attached to the organic structure (the C-H backbone) are what effect the solubilities.Like carboxylic acids and alcohols form hydrogen bonds with the water, helping to solubilize it.
3. Take alcohols for example: methanol, ethanol, and isopropanol are all completely soluble in water. By the time you get to butanol and some of the larger alcohols, including those with more complex structures, they tend to be less soluble.
