You have to use the Henderson-Hasselbalch equation. Keep in mind that because the Pka is given the equation changes form slightly:
PH = Pka + log[acid/base]
Step 1 (Figure out the concentrations):
0.282 M of Acid (C6H5OOH) - 0.150 M = 0.132 M of acid
0.282 M of Base (C6HCOO) + 0.150 M = 0.432 M of bas3
Step 2 (Plug into equation):
PH = Pka + log[acid/base]
PH = 4.20 + log[0.132 M/0.432 M]
PH = 3.69
Write out the eqn of magnesium and oxygen. this should be under “metals” chapter. do revise.
next, find the mols of both oxygen and magnesium. compare the ratios and find the LIMITING REAGENT.
use the mols of the limiting reagent to compare with the mols of the product.
take the mols of the product/mr of the product.
this will give u the mass.
Answer:
Explanation:
Given parameters:
Mass of CuCl₂ = 2.50g
Mass of Al = 0.50g
Unknown:
Number of moles of CuCl₂ and Al = ?
Solution:
To solve this problem, we must understand that the number of moles is a fundamental property used in stoichiometry calculations.
Number of moles = 
Molar mass of CuCl₂ = 63.6 + 2(35.5) = 134.5g/mole
Molar mass of Al = 26.98g/mole
Number of moles of CuCl₂ = 
= 0.019moles
Number of moles of Al = 
= 0.019moles
Answer:
<h3>D. c = fλ</h3>
Explanation:
c = fλ
where" c "is the speed of light ,
• "f" is the frequency of the electromagnetic waves,
• " λ" is its wavelength.
Global win I think brace it say around small areas
