a. 48.6 is magnesium and 32.0 is oxygen
b. 80.6
c. also 80.6
d. yes, because the product has equal mass to the reactants
Answer: 1.5 moles
Explanation: one mole Zn uses 2 moles HCl.
1.5 moles Zn uses 3.0 mol HCl. Then Zn is a limiting reactant
And produces equal amount of H2.
<u>Answer:</u>
density of solid = 4.5 g/cm³
<u>Explanation:</u>
density = mass ÷ volume
• We know the mass of the object (135 g). We need to calculate the volume:
Volume = length × width × thickness
= 5 cm × 3 cm × 2 cm
= 30 cm³
• Now we can calculate the solid's density:
density = 135 g ÷ 30 cm³
= 4.5 g/cm³
Hello!
We have the following data:
ps: we apply Ka in benzoic acid to the solution.
[acid] = 0.235 M (mol/L)
[salt] = 0.130 M (mol/L)
pKa (acetic acid buffer) =?
pH of a buffer =?
Let us first find pKa of benzoic acid, knowing that Ka (benzoic acid) = 
So:





Now, using the abovementioned data for the pH formula of a buffer solution or (Henderson-Hasselbalch equation), we have:
![pH = pKa + log\:\dfrac{[salt]}{[acid]}](https://tex.z-dn.net/?f=%20%20pH%20%3D%20pKa%20%2B%20log%5C%3A%5Cdfrac%7B%5Bsalt%5D%7D%7B%5Bacid%5D%7D%20%20%20)





Note:. The pH <7, then we have an acidic solution.
I Hope this helps, greetings ... DexteR! =)