Do you still need the answer for these ? if so , i have them
<span>The effective nuclear charge of an atom = total electrons - inner electrons
For O, ENC = 8 - 2 = 6
For Li, ENC = 3 - 2 = 1
For C, ENC = 6 - 2 = 4
The electrons in O experience the greatest effective nuclear charge and that is why O is smaller than C (which is smaller than Li).</span>
Answer:
partial pressure of gas D Pd = 15.5 kPa
Explanation:
As per the Dalton's law of partial pressure, in a mixture, pressure exerted by each gas when summed gives the total partial pressure exerted by mixture.
P(Total) = P1+P2+P3.....
Given P(Total) = 35.7 kPa
Partial pressure of gas A Pa = 7.8 kPa
Partial pressure of gas B Pb = 3.7 kPa
Partial pressure of gas C Pc = 8.7 kPa
There, Partial pressure of gas D Pd = P(Total) -(Pa+Pb+Pc)
Pd = 35.7-(7.8+3.7+8.7) = 35.7-20.2 kPa = 15.5 kPa
Therefore, partial pressure of gas D Pd = 15.5 kPa
Percentage Yield = (Actual Yield ÷ Theoretical Yield) × 100
The Actual Yield is given in the question as 21.2 g of NaCl. However, in order to find the theoretical yield, you have to write a balanced equation and use the mole ratio to calculate the mass of NaCl that would be produced.
Balanced Equation: CuCl + NaNO₃ → NaCl + CuNO₃
Moles of CuCl = Mass of CuCl ÷ Molar Mass of CuCl
= 31.0 g ÷ (63.5 + 35.5)g/mol
= 0.31 mol
the mole ratio of CuCl to NaCl is 1 : 1,
∴ if moles of CuCl = 0.31 mol,
then moles of NaCl = 0.31 mol
Now, Mass of NaCl = Moles of NaCl × Molar Mass of NaCl
= 0.31 mol × (23 + 35.5) g/mol
= 18.32 g
⇒ the THEORETICAL Yield of NaCl, in this case, is 18.32 g.
Now, since Percentage Yield = (Actual Yield ÷ Theoretical Yield) × 100
⇒ Percentage Yield of NaCl = (21.2g ÷ 18.32g) × 100
= 115.7 %
NOTE: Typically, the percentage yield of a reaction is less than 100%, however in a case where the mass of the substance is weighed with impurities, then that mass may be in excess of 100% as seen here.
