Answer:
B.Convection
the movement caused within a fluid by the tendency of hotter and therefore less dense material to rise, and colder, denser material to sink under the influence of gravity, which consequently results in transfer of heat.
Here the base is a benzoate ion, which is a weak base and reacts with water.
The equation indicates that for every mole of OH- that is produced , there is one mole of C6H5COOH produced.
Therefore [OH-] = [C6H5COOH]
In the question value of PH is given and by using pH we can calculate pOH and then using pOH we can calculate [OH-]
pOH = 14 - pH
pH given = 9.04
pOH = 14-9.04 = 4.96
pOH = -log[OH-] or ![[OH^{-}] = 10^{^{-pOH}}](https://tex.z-dn.net/?f=%20%5BOH%5E%7B-%7D%5D%20%3D%2010%5E%7B%5E%7B-pOH%7D%7D%20)
![[OH^{-}] = 10^{^{-4.96}}](https://tex.z-dn.net/?f=%20%5BOH%5E%7B-%7D%5D%20%3D%2010%5E%7B%5E%7B-4.96%7D%7D%20)
![[OH^{-}] = 1.1\times 10^{-5}](https://tex.z-dn.net/?f=%20%5BOH%5E%7B-%7D%5D%20%3D%201.1%5Ctimes%2010%5E%7B-5%7D%20)
The base dissociation equation kb = 
![kb =\frac{[C6H5COOH][OH^{-}]}{[C6H5COO^{-}]}](https://tex.z-dn.net/?f=%20kb%20%3D%5Cfrac%7B%5BC6H5COOH%5D%5BOH%5E%7B-%7D%5D%7D%7B%5BC6H5COO%5E%7B-%7D%5D%7D)
H2O(l) is not included in the 'kb' equation because 'solid' and 'liquid' are taken as unity that is 1.
Value of Kb is given = 
And value of [OH-] we have calculated as 
and value of C6H5COOH is equal to OH-
Now putting the values in the 'kb' equation we can find the concentration of C6H5COO-
![1.6\times 10^{-10} = \frac{[1.1\times 10^{-5}][1.1\times 10^{-5}]}{[C6H5COO^{-}]}](https://tex.z-dn.net/?f=%201.6%5Ctimes%2010%5E%7B-10%7D%20%3D%20%5Cfrac%7B%5B1.1%5Ctimes%2010%5E%7B-5%7D%5D%5B1.1%5Ctimes%2010%5E%7B-5%7D%5D%7D%7B%5BC6H5COO%5E%7B-%7D%5D%7D%20)
![[C6H5COO^{-}] = \frac{[1.1\times 10^{-5}][1.1\times 10^{-5}]}{1.6\times 10^{-10}}](https://tex.z-dn.net/?f=%20%5BC6H5COO%5E%7B-%7D%5D%20%3D%20%5Cfrac%7B%5B1.1%5Ctimes%2010%5E%7B-5%7D%5D%5B1.1%5Ctimes%2010%5E%7B-5%7D%5D%7D%7B1.6%5Ctimes%2010%5E%7B-10%7D%7D%20)
![[C6H5COO^{-}] = 0.76 M](https://tex.z-dn.net/?f=%20%5BC6H5COO%5E%7B-%7D%5D%20%3D%200.76%20M%20)
or 
So, Concentration of NaC6H5COO would also be 0.76 M and volume is given to us 0.50 L , now moles can we calculated as : Moles = M X L
Moles of NaC6H5COO would be = 
Moles of NaC6H5COO (sodium benzoate) = 0.38 mol
Answer:
+375.2 KJ.
Explanation:
The balanced equation for the reaction is given below:
H₂ + F₂ —> 2HF ΔH = +536 KJ
From the balanced equation above,
2 moles of HF required +536 KJ .
Finally, we shall determine the heat required to produce 1.4 mol of hydrogen fluoride, HF. This is illustrated below:
From the balanced equation above,
2 moles of HF required +536 KJ .
Therefore, 1.4 moles of HF will require = (1.4 × 536)/2 = +375.2 KJ
Thus, +375.2 KJ of heat energy is required.
Answer:
C: Good conductors of electricity
Explanation:
By definition, Metals have metallic bonds and thus they are good conductors of electricity due to the fact that their electrons in the electron sea are usually free to flow and carry electric current. Thus, the correct answer is option C.
Answer:
87.5 % is the percent yield
Explanation:
We convert the mass of H₂ to moles: 4 g / 2g/mol = 2 moles of H₂
The reaction is: CO(g) + 2H₂(g) → CH₃OH(l)
So ratio is 2:1. Therefore, If I have 2 moles of hydrogen I would produce 1 mol of methanol.
So, as molar mass of methanol is 32g/mol; 32 g is the mass of produced methanol, at the 100 % yield reaction (theoretical yield)
Percent yield will be: (produced yield/ theoretical yield) . 100
(28 g / 32g) . 100 = 87.5 %
