Answer:
.224 M
Explanation:
To begin, we need to find the molar mass of Na2S
To find Molarity, we use the equation M=moles/Liters of solution
We are given grams, so we must divide by the molar mass of Na2S to find moles.
- 8.76g Na2S / 78.05g/mol Na2S= .112 moles
Now we use our Molarity equation:
- .112 moles Na2S / .500L of solution = .224 M
Molality of solution = 0.529 m
mass solvent in kg = 20.6 g => 20.6 / 1000 => 0.0206 kg
number of moles = molality x mass solvent
= 0.529 x 0.0206 => <span> 0.0108 mol benzene
</span>
hope this helps!
Answer:
Nonpoint-source-pollution
Explanation:
Answer:
The correct answer is
B.action potential; sodium
Explanation:
Action potential
Nerve action potentials are initiated and propagated in an all or nothing fashion. The all-or nothing action potential is initiated when the membrane potential threshold value is reached
Sodium
Voltage-gated Na⁺ ions membrane channels open enabling an influx of sodium ions to rapidly enter the cell, raising the membrane potential up to +40 mV
Depolarization in the neuron is based ion exchange channels opening to allow the rapid influx of sodium ions (Na⁺) and the efflux of potassium ions (K⁺)
The neuronal responds rapidly and for short periods to the activation of an ion channel receptor by a drug or natural neurotransmitter is rapid rel
Answer:
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Explanation:
A <em>first order reaction</em> follows the law:
![rate=k[A]](https://tex.z-dn.net/?f=rate%3Dk%5BA%5D)
, where [A] is the concentraion of the reactant A.
Equivalently:
![\dfrac{d[A]}{dt}=-k[A]](https://tex.z-dn.net/?f=%5Cdfrac%7Bd%5BA%5D%7D%7Bdt%7D%3D-k%5BA%5D)
Integrating:
![\dfrac{d[A]}{[A]}=-kdt](https://tex.z-dn.net/?f=%5Cdfrac%7Bd%5BA%5D%7D%7B%5BA%5D%7D%3D-kdt)
![\ln \dfrac{[A]}{[A_o]}=-kt](https://tex.z-dn.net/?f=%5Cln%20%5Cdfrac%7B%5BA%5D%7D%7B%5BA_o%5D%7D%3D-kt)
Half-life means [A]/[A₀] = 1/2, t = t½:
That means that the half-life is constant.
The slope of the plot of ln [N₂O₅] is -k. Then k is equal to 6.40 × 10⁻⁴ min⁻¹.
Thus, you can calculate t½:
t½ = ln(2) / 6.40 × 10⁻⁴ min⁻¹
t½ = 1,083 min.
Rounding to 3 significant figures, that is 1,080 min.
