Answer:
24g of NaOH are required
Explanation:
Molarity, M, is an unit of concentration widely used in chemistry defined as the ratio between moles of solute (In this case, NaOH), and volume of solution in liters.
We can find the moles of NaOH and its mass with the volume and desired concentration as follows:
<em>Moles NaOH:</em>
400.0mL = 0.400L * (1.50mol / L) = 0.600 moles NaOH
<em>Mass NaOH -Molar mass: 40.0g/mol-:</em>
0.600 moles * (40.0g / mol) =
<h3>24g of NaOH are required</h3>
It's 1. Melting a substance. The rest are chemical changes
.50 M KCl because 5% is the same as .05, which makes the .50M more concentrated.
Data Given:
Time = t = ?
Current = I = 10 A
Faradays Constant = F = 96500
Chemical equivalent = e = 107.86/1 = 107.86 g
Amount Deposited = W = 17.3 g
Solution:
According to Faraday's Law,
W = I t e / F
Solving for t,
t = W F / I e
Putting values,
t = (17.3 g × 96500) ÷ (10 A × 107.86 g)
t = 1547.79 s
t = 1.54 × 10³ s
Answer:
Molar absorptivity or molar extinction co-effecient = 2120.14 cm⁻¹M⁻¹
Explanation:
First convert Concentration from ppm inM or mol/l
⇒ Molar mass of KMnO₄ = 158.03 g
⇒ 4.48 ppm = 4.48 mg/l = 4.48 x 10⁻³ g/l
⇒ Molarity =
= 2.83 x 10⁻⁵ molar
Absorbance (A) = - log(T) ( T = % transmittance)
= - log(0.859)
= 0.06
According to Lambert Beer's law
ε = 
or, ε = 
or, ε = 2120.14 cm⁻¹M⁻¹
Where
ε = Molar absorptivity
A = absorbance
C = Molar concentration of KMnO₄ solution
l = length