Answer:
a. pH = 13.50
b. pH = 13.15
Explanation:
Hello!
In this case, since the undergoing chemical reaction between KOH and HBr is:
As they are both strong. In such a way, since the initial analyte is the 25.00 mL solution of 0.320-M KOH, we first compute the pOH it has, considering that all the KOH is ionized in potassium and hydroxide ions:
![pOH=-log([OH^-])=-log(0.320)=0.50](https://tex.z-dn.net/?f=pOH%3D-log%28%5BOH%5E-%5D%29%3D-log%280.320%29%3D0.50)
Thus, the pH is:
Which is the same answer for a and b as they ask the same.
Moreover, once 5.00 mL of the HBr is added, we need to compute the reacting moles of each substance:
It means that since there are more moles of KOH, we need to compute the remaining moles after those 0.00375 moles of acid consume 0.00375 moles of base because they are in a 1:1 mole ratio:
Next, we compute the resulting concentration of hydroxide ions (equal to the concentration of KOH) in the final solution of 30.00 mL (25.00 mL + 5.00 mL):
![[OH^-]=[KOH]=\frac{0.00425mol}{0.03000L}=0.142M](https://tex.z-dn.net/?f=%5BOH%5E-%5D%3D%5BKOH%5D%3D%5Cfrac%7B0.00425mol%7D%7B0.03000L%7D%3D0.142M)
So the pOH and the pH turn out:
Best regards!
Answer:
The answer is definitely D
Explanation:
Answer:
The two statements are all True for group 7 and 8 elements.
Explanation:
The Group 7 elements are known as the halogens. They are reactive non-metals and are always found in compounds with other elements. Chlorine, bromine and iodine are all halogens.
Chlorine, bromine and iodine are the three common Group 7 elements. Group 7 elements form salts when they react with metals. The term ‘halogen’ means 'salt former'.
In addition to the discription given to norble gases in the question which is true, norble gases;
- are inert gases located on the right of the periodic table.
- have a full-set of valence electrons, so they're stable, unreactive
- are colorless, odorless and tasteless.
- have low melting and low boiling points.
- can be found in small amounts in the Earth's crust and the Earth's atmosphere.
Answer:
Ⓑ Both plants and animals release energy from glucose/sugar in cellular respiration.
