Answer:
Concentration of sulfuric acid in the acid rain sample is 0.0034467 mol/L.
Explanation:
Volume of NaOH = 1.7 ml = 0.0017 L
Molarity of NaOH = 0.0811 M
Moles of NaOH = n
n = 0.0001378 mol

According to reaction, 2 mol of NaOH neutralize 1 mol of sulfuric acid.
Then 0.0001378 mol of NaOH will neutralize:
of sulfuric acid.
Concentration of sulfuric acid in the acid rain sample: x

Concentration of sulfuric acid in the acid rain sample is 0.0034467 mol/L.
<u>Given:</u>
Concentration of Ba(OH)2 = 0.348 M
<u>To determine:</u>
pOH of the above solution
<u>Explanation:</u>
Based on the stoichiometry-
1 mole of Ba(OH)2 is composed of 1 mole of Ba2+ ion and 2 moles of OH- ion
Therefore, concentration of OH- ion = 2*0.348 = 0.696 M
pOH = -log[OH-] = - log[0.696] = 0.157
Ans: pOH of 0.348M Ba(OH)2 is 0.157
Answer:
8.09x10⁻⁵M of Fe³⁺
Explanation:
Using Lambert-Beer law, the absorbance of a sample is proportional to its concentration.
In the problem, the Fe³⁺ is reacting with KSCN to produce Fe(SCN)₃ -The red complex-
The concentration of Fe³⁺ in the reference sample is:
4.80x10⁻⁴M Fe³⁺ × (5.0mL / 50.0mL) = 4.80x10⁻⁵M Fe³⁺
<em>Because reference sample was diluted from 5.0mL to 50.0mL.</em>
<em>That means a solution of 4.80x10⁻⁵M Fe³⁺ gives an absorbance of 0.512</em>
Now, as the sample of the lake gives an absorbance of 0.345, its concentration is:
0.345 × (4.80x10⁻⁵M Fe³⁺ / 0.512) = <em>3.23x10⁻⁵M. </em>
As the solution was diluted from 20.0mL to 50.0mL, the concentration of Fe³⁺ in Jordan lake is:
3.23x10⁻⁵M Fe³⁺ × (50.0mL / 20.0mL) = <em>8.09x10⁻⁵M of Fe³⁺</em>
Answer: 91.73g of NaCl
Explanation:
First, we solve for the number of moles of F2 using the ideal gas equation
V = 12L
P = 1.5 atm
T = 280K
R = 0.082atm.L/mol/K
n =?
PV = nRT
n = PV /RT
n = (1.5x12)/(0.082x280)
n = 0.784mol
Next, we convert this mole ( i.e 0.784mol) of F2 to mass
MM of F2 = 19x2 = 38g/mol
Mass conc of F2 = n x MM
= 0.784 x 38 = 29.792g
Equation for the reaction is given below
F2 + 2NaCl —> 2NaF + Cl2
Molar Mass of NaCl = 23 + 35.5 = 58.5g/mol
Mass conc. of NaCl from the equation = 2 x 58.5 = 117g
Next, we find the mass of NaCl that reacted with 29.792g of F2.
From the equation,
38g of F2 redacted with 117g of NaCl.
Therefore, 29.792g of F2 will react with Xg of NaCl i.e
Xg of NaCl = (29.792 x 117)/38
= 91.73g
Therefore, 91.73g of NaCl reacted with f2
11 lb = 4.99 kg.
So, 74.85 mg should be given to the infant. Thus 0.75 mL of the suspension should be given.