Answer:
2.99×10²⁵ molecules of CO₂ are produced
Explanation:
Decomposition reaction is:
Ca(HCO₃)₂ => CaO(s) + 2CO₂(g) + H₂O(g)
Ratio is 1:2. Let's make a rule of three:
1 mol of bicarbonate can produce 2 moles of CO₂
Therefore, 24.9 moles of bicarbonate may produce, 49.8 moles (24.9 .2 )/1
Let's determine the number of molecules
1 mol has 6.02×10²³ molecules
49.8 moles must have (49.8 . 6.02×10²³) / 1 = 2.99×10²⁵ molecules
Answer:
0.01 moles of SrCO₃
Explanation:
In this excersise we need to propose the reaction:
K₂CO₃ + Sr(NO₃)₂ → 2KNO₃ + SrCO₃
As we only have data about the potassium carbonate we assume the strontium nitrite as the excess reactant.
1 mol of K₂CO₃ react to 1 mol of Sr(NO₃)₂ in order to produce 2 moles of potassium nitrite and 1 mol of strontium carbonate.
Ratio is 1:1. In conclussion,
0.01 mol of K₂CO₃ must produce 0.01 moles of SrCO₃
Explanation:
The given reaction is as follows.

Hence, number of moles of NaOH are as follows.
n = 
= 0.005 mol
After the addition of 25 ml of base, the pH of a solution is 3.62. Hence, moles of NaOH is 25 ml base are as follows.
n = 
= 0.0025 mol
According to ICE table,

Initial: 0.005 mol 0.0025 mol 0 0
Change: -0.0025 mol -0.0025 mol +0.0025 mol
Equibm: 0.0025 mol 0 0.0025 mol
Hence, concentrations of HA and NaA are calculated as follows.
[HA] = 
[NaA] = 
![[A^{-}] = [NaA] = \frac{0.0025 mol}{V}](https://tex.z-dn.net/?f=%5BA%5E%7B-%7D%5D%20%3D%20%5BNaA%5D%20%3D%20%5Cfrac%7B0.0025%20mol%7D%7BV%7D)
Now, we will calculate the
value as follows.
pH = 
![pK_{a} = pH - log \frac{[A^{-}]}{[HA]}](https://tex.z-dn.net/?f=pK_%7Ba%7D%20%3D%20pH%20-%20log%20%5Cfrac%7B%5BA%5E%7B-%7D%5D%7D%7B%5BHA%5D%7D)
= 
= 3.42
Thus, we can conclude that
of the weak acid is 3.42.