0.042 moles of Hydrogen evolved
<h3>Further explanation</h3>
Given
I = 1.5 A
t = 1.5 hr = 5400 s
Required
Number of Hydrogen evolved
Solution
Electrolysis of water ⇒ decomposition reaction of water into Oxygen and Hydrogen gas.
Cathode(reduction-negative pole) : 2H₂O(l)+2e⁻ ⇒ H₂(g)+2OH⁻(aq)
Anode(oxidation-positive pole) : 2H₂O(l)⇒O₂(g)+4H⁻(aq)+4e⁻
Total reaction : 2H₂O(l)⇒2H₂(g)+O₂(g)
So at the cathode H₂ gas is produced
Faraday : 1 mole of electrons (e⁻) contains a charge of 96,500 C
Q = i.t
Q = 1.5 x 5400
Q = 8100 C
mol e⁻ = 8100 : 96500 = 0.084
From equation at cathode , mol ratio e⁻ : H₂ = 2 : 1, so mol H₂ = 0.042
Answer:
The initial temperature of the metal is 84.149 °C.
Explanation:
The heat lost by the metal will be equivalent to the heat gain by the water.
- (msΔT)metal = (msΔT)water
-32.5 grams × 0.365 J/g°C × ΔT = 105.3 grams × 4.18 J/g °C × (17.3 -15.4)°C
-ΔT = 836.29/12.51 °C
-ΔT = 66.89 °C
-(T final - T initial) = 66.89 °C
T initial = 66.89 °C + T final
T initial = 66.89 °C + 17.3 °C
T initial = 84.149 °C.
Answer: D, splitting water into hydrogen and oxygen is a chemical change.
Answer:
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Explanation:
Step 1
The osmotic pressure is calculated as follows:
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Step 2
<em>Information provided:</em>
The mass of solute = 13.6 g
Volume of solution = 251 mL
Absolute temperature = T = 298 K
The molar mass of solute = M = 354.5 g/mol
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Step 3
Procedure:
1 L = 1000 mL => Volume = 251 mL x (1 L/1000 mL) = 0.251 L
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C = moles of solute/volume of solution (L)
C = mass of solute/(molar mass x Volume (L))
C = 13.6 g/(354.5 g/mol x 0.251 L)
C = 0.153 mol/L
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π = C x R x T
π = 0.153 mol/L x 0.082 atm L/mol K x 298 K
π = 3.74 atm
Answer: π = 3.74 atm
