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.
Answer:
7. 4H₂O
Elements: Hydrogen, Oxygen
Number of molecules: 4
Number of elements: 8 H, 4 O
Number of Atoms: 12
Explanation:
The elements are determined by the their symbol i.e. H = hydrogen.
The number of molecules is determined by the coefficient ( the number in front of everything, in this case 4).
The number of elements is determined by the coefficient and the subscripts. Multiply the coefficient by the subscript after each element. When there is no subscript, it is equal to 1. 4H₂ = 4x2 = 8; 4O = 4x1 = 4.
The number of atoms is all the individual elements added together. 8+4 = 12.
1. This is a combustion reaction.<span>
<span>Combustion reactions can happen with the </span>presence of O</span>₂ <span>gas. O₂<span>
reacts with another element or compound and </span></span>oxidize<span> it. Here ethanol reacts with O₂<span> and produces </span></span>CO₂ and H₂O as products.<span> <span>Combustion is also called as </span></span>burning. <span>
2.
Reaction will shift to right. <span>
</span><span>If more CH</span>₃CH₂OH is added to the system, then the</span> amount of CH₃CH₂OH will increase.<span> <span>Then the equilibrium in the system </span></span>will be broken.<span> <span>To make the equilibrium again, the </span></span>added CH₃CH₂OH should be removed.<span> To do that system will consume more CH</span>₃CH₂<span>OH to make products which helps to decrease
the amount of ethanol. Hence,
the reaction will shift to right.<span>
3. The reaction
will shift to right.</span><span>
</span><span>If the water is extracted from the system, the </span>amount of water will decrease. <span>That means the </span>amount of products decrease. Then the system will try to gain equilibrium by increasing the water. To increase water the forward reaction should be enhanced. <span>Hence, the</span> reaction will shift to right.<span>
4. The reaction
will shift to right.
</span><span>This is an </span>exothermic reaction <span>since it </span>produces heat. If the produced heat is removed, then the system will be cold. To maintain the temperature, system has to increase the amount of heat produced. Then, the forward reaction should be
enhanced. Hence, the reaction
will shift to right.<span>
5. The Le
Chatelier's principle.
</span>Le Chatelier's principle says if a
condition changes in a system which was in an equilibrium state, the system
will try to gain equilibrium by correcting the changed condition back to
normal. Most of industries which make
chemicals use this principle</span>
Because that solid is frozen liquid, so when it gets heated up, it will melt. Like Ice.
Hope I Helped! :)
