Answer:
pH = 10.505
Explanation:
Molar mass of Amphetamine ( C9H13N) = 135 g/mol
Given that the concentration of Amphetamine = 225 mg/L
mass of Amphetamine in one Liter = 
= 0.225 g
Number of moles of Amphetamine in one liter =
= 0.001667 mol
∴ molarity = 0.0017 M
C₉H₁₃N + H₂O --------> C₉H₁₃NH⁺ + OH⁻
I(M) 0.001667 M 0 0
C(M) -x x x
E(M) 0.001667 - x x x
Pkb = -log Kb = 4.2
∴ Kb = 6.309 x 10⁻⁵
Kb = 6.309 x 10⁻⁵
Equilibrium constant = [C₉H₁₃NH⁺][OH⁻]/ [C₉H₁₃N]
6.309 x 10⁻⁵ = x² / 0.001667-x
where 0.001667 -x ≅ 0.001667
Then;
x² = 6.309 x 10⁻⁵ × 0.001667
x² = 1.0517103 × 10⁻⁷
x = 
x = 0.00032 M
x = [OH-] = 0.00032 M
∴ pOH = -log [OH-]
pOH = -log (0.00032)
pOH =3.495
pH = 14 - 3.495
= 10.505
Answer:
14.91 K.
Explanation:
- To solve this problem, we can use the following relation:
<em>Q = m.c.ΔT,</em>
where, Q is the amount of heat transferred to water.
m is the mass of the amount of water (m = 2.0 kg = 2000.0 g).
c is the specific heat capacity of water (c = 4.2 J/g.K).
ΔT is the change in temperature due to the transfer of butane burning.
- To determine Q that to be used in calculation:
Q from 4.000 g of butane is completely burned is - 198.3 kJ = 198300 J.
<em>The negative sign</em><em> symbolizes the the enthalpy change is </em><em>exothermic</em><em>, which means that </em><em>the</em><em> </em><em>energy is released</em><em>.
</em>
- Note that only 63.15% of the energy generated is actually transferred to the water.
∴ Q (the amount of heat transferred to water) = (198300 J)(0.6315) = 125226.45 J.
- Now, we can obtain the change in temperature:
∴ ΔT = Q/m.c. = (125226.45 J) / (2000.0 g)(4.2 J/g.K) = 14.9079 K ≅ 14.91 K.
<em>This means that the temperature is increased by 14.91 K.</em>
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What are the options? but the constants I know for sure are 22.4L the molar mass of an ion . I just need to know the options
You can use <span>vulcanized rubber and nylon to make rope. hope it helps:)</span>
In viewing a chemical equation,we <span>determine the ratios that relate reactants and products </span>from the coefficients of the reactants and products .
