Answer:
37.9g of carbon 14 remains
Explanation:
The radioactive decay of an atom follows the equation:
Ln[A] = -kt + Ln[A]₀
<em>Where [A] is amount of isotope after time t, k is decay constant and [A]₀ initial amount of the isotope.</em>
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We can find k from half-life using:
k = ln 2 / Half-Life
k = ln 2 / 5730 years
k = 1.2097x10⁻⁴ yrs⁻¹
Replacing in the equation all values:
Ln[A] = -1.2097x10⁻⁴ yrs⁻¹*2292yrs + Ln[50g]
Ln[A] = 3.635
[A] = 37.9g of carbon 14 remains
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Answer:
True...I think I'm not sure
The statement that best explains why heating a liquid affects its viscosity is that "The molecules move faster at higher temperatures and overcome attractions more easily."<span>. Remember that viscosity is a physical property of the fluids that measure the resistance (opposition) to flow and it, generally decreases, as the temperature increases and the intermolecular force decrease.</span>
Answer:
174.8 g/m is the molar mass of the solute
Explanation:
We must apply colligative property of freezing point depression.
ΔT = Kf . m . i
ΔT = T° freezing pure solvent - T° freezing solution (0° - (-2.34°C) = 2.34°C
Kf = Fussion constant for water, 1.86 °C/m
As ascorbic acid is an organic compound, we assume that is non electrolytic, so i = 1
2.34°C = 1.86°C/m . m
2.34°C / 1.86 m/°C = 1.26 m
This value means the moles of vitamin C, in 1000 g of solvent
We weighed the solute in 250 g of solvent, so let's calculate the moles of vitamin C.
1000 g ___ 1.26 moles
In 250 g ___ (250 . 1.26)/1000 = 0.314 moles
This are the moles of 55 g of ascorbic acid, so the molar mass, will be:
grams / mol ⇒ 55 g/0.314 m = 174.8 g/m
