Answer:
The number before any molecular formula applies to the entire formula. So here you have five molecules of water with two hydrogen atoms and one oxygen atom per molecule. Thus you have ten hydrogen atoms and five oxygen atoms in total.
Answer:
The answer is 0.01 M
Explanation:
The problem is solved by applying the expression for ionic product of water as follows:
Kw = [H₃O⁺] [OH⁻]
Where Kw is the ionic product of water and it is 1.10⁻¹⁴ M at⁴ 25ºC. As [OH⁻]= 1.10⁻¹² M, [H₃O⁺] will be:
[H₃O⁺]= Kw/ [OH⁻]= 1.10⁻¹⁴M/1.10⁻¹²M= 0.01 M
Answer:
1.76 moles of HCl.
Explanation:
We'll begin by writing the balanced equation for the reaction. This is illustrated below:
2KMnO₄ + 8HCl —> 3Cl₂ + 2MnO₂ + 4H₂O + 2KCl
From the balanced equation above,
2 moles of KMnO₄ reacted with 8 moles of HCl.
Finally, we shall determine the number of mole of HCl needed to react with 0.44 moles of KMnO₄. This can be obtained as follow:
From the balanced equation above,
2 moles of KMnO₄ reacted with 8 moles of HCl.
Therefore, 0.44 moles of KMnO₄ will react with = (0.44 × 8)/2 = 1.76 moles of HCl.
Thus, 1.76 moles of HCl is needed for the reaction.
You can tell if each side of the equation has the same molar mass.
Answer:
b. 
Explanation:
Hello there!
In this case, given the ionization reaction of HClO as weak acid:
We can write the equilibrium expression as shown below:
![Ka=3.5x10^{-8}=\frac{[H^+][ClO^-]}{[HClO]}](https://tex.z-dn.net/?f=Ka%3D3.5x10%5E%7B-8%7D%3D%5Cfrac%7B%5BH%5E%2B%5D%5BClO%5E-%5D%7D%7B%5BHClO%5D%7D)
In such a way, via the definition of x as the reaction extent, we can write:
![3.5x10^{-8}=\frac{x^2}{[HClO]}](https://tex.z-dn.net/?f=3.5x10%5E%7B-8%7D%3D%5Cfrac%7Bx%5E2%7D%7B%5BHClO%5D%7D)
As long as Ka<<<<1 so that the x on the bottom can be neglected. Thus, we solve for x as shown below:
And finally the percent dissociation:
![\% diss=\frac{x}{[HClO]} *100\%\\\\\% diss=\frac{7.94x10^{-5}M}{0.18}*100\% \\\\\% diss =0.044\%=4.4x10^{-2}\%](https://tex.z-dn.net/?f=%5C%25%20diss%3D%5Cfrac%7Bx%7D%7B%5BHClO%5D%7D%20%2A100%5C%25%5C%5C%5C%5C%5C%25%20diss%3D%5Cfrac%7B7.94x10%5E%7B-5%7DM%7D%7B0.18%7D%2A100%5C%25%20%5C%5C%5C%5C%5C%25%20diss%20%3D0.044%5C%25%3D4.4x10%5E%7B-2%7D%5C%25)
Which is choice b.
Best regards!
