Answer : The correct option is, (D) 100 times the original content.
Explanation :
As we are given the pH of the solution change. Now we have to calculate the ratio of the hydronium ion concentration at pH = 5 and pH = 3
As we know that,
![pH=-\log [H_3O^+]](https://tex.z-dn.net/?f=pH%3D-%5Clog%20%5BH_3O%5E%2B%5D)
The hydronium ion concentration at pH = 5.
![5=-\log [H_3O^+]](https://tex.z-dn.net/?f=5%3D-%5Clog%20%5BH_3O%5E%2B%5D)
![[H_3O^+]=1\times 10^{-5}M](https://tex.z-dn.net/?f=%5BH_3O%5E%2B%5D%3D1%5Ctimes%2010%5E%7B-5%7DM)
..............(1)
The hydronium ion concentration at pH = 3.
![3=-\log [H_3O^+]](https://tex.z-dn.net/?f=3%3D-%5Clog%20%5BH_3O%5E%2B%5D)
![[H_3O^+]=1\times 10^{-3}M](https://tex.z-dn.net/?f=%5BH_3O%5E%2B%5D%3D1%5Ctimes%2010%5E%7B-3%7DM)
................(2)
By dividing the equation 1 and 2 we get the ratio of the hydronium ion concentration.
![\frac{[H_3O^+]_{original}}{[H_3O^+]_{final}}=\frac{1\times 10^{-5}}{1\times 10^{-3}}=\frac{1}{100}](https://tex.z-dn.net/?f=%5Cfrac%7B%5BH_3O%5E%2B%5D_%7Boriginal%7D%7D%7B%5BH_3O%5E%2B%5D_%7Bfinal%7D%7D%3D%5Cfrac%7B1%5Ctimes%2010%5E%7B-5%7D%7D%7B1%5Ctimes%2010%5E%7B-3%7D%7D%3D%5Cfrac%7B1%7D%7B100%7D)
![100\times [H_3O^+]_{original}=[H_3O^+]_{final}](https://tex.z-dn.net/?f=100%5Ctimes%20%5BH_3O%5E%2B%5D_%7Boriginal%7D%3D%5BH_3O%5E%2B%5D_%7Bfinal%7D)
From this we conclude that when the pH of a solution changes from a pH of 5 to a pH of 3, the hydronium ion concentration is 100 times the original content.
Hence, the correct option is, (D) 100 times the original content.
Answer:
Explanation:
We are given the mass, specific heat, and temperature, so we must use this formula for heat energy.
The mass is 5 grams, the specific heat capacity is 0.14 Joules per gram degree Celsius. Let's find the change in temperature.
- ΔT= final temperature - initial temperature
- ΔT= 95°C - 15°C = 80°C
We know the variables and can substitute them into the formula.
Multiply the first numbers. The grams will cancel.
Multiply again. This time the degrees Celsius cancel.
56 Joules of heat are needed.
Answer:
The correct answer will be "
".
Explanation:
We have:
Moles of solute (Na₂Co₃) = 
= 
= 
Now,
The volume of the solution will be:
⇒ 
∴ 
The formula to find the concentration will be:
⇒ 
On substituting the given values, we get
⇒ 
⇒ 
The correct answer is A
The octet rule state that all main group elements form bonds such that they achieve a noble gas configuration with eight valence electrons. In this case carbon has 4 electrons in its outermost shell and requires 4 more electrons to achieve an octet. Hydrogen is an exception to the octet rule and it only requires two electrons to achieve an octet. All the other options have C and H forming bonds that do not lead to a noble gas configuration.
