The general equation for radioactive decay is;
N = N₀e^(-λt)
x - decay constant (λ) - rate of decay
t- time
N - amount remaining after t days , since we are calculating the half life, amount of time it takes for the substance to to be half its original value, its N₀/2
N₀ - amount initially present
substituting the values
N₀/2 = N₀e^(-0.081t)
0.5 = e^(-0.081t)
ln (0.5) = -0.081t
-0.693 = -0.081t
t = 0.693 / 0.081
= 8.55
half life of substance is 8.55 days
Question:<u> As the sun heats the surface of the ocean, two layers of water result. What separates the layers.?</u>
Answer: <u>The Thermocline </u>
<em>Hope this helps!.</em>
<em>~~~~~~~~~~~~~~~~~~~</em>
<em>~A.W~ZoomZoom44</em>
Answer:
0.12M
Explanation:
A balanced equation for the reaction will go a great deal in obtaining our desired result. So, let us write a balanced equation for the reaction
HCl + NaOH —> NaCl + H2O
From the above equation,
nA (mole of the acid) = 1
nB (mole of the base) = 1
Data obtained from the question include:
Vb (volume of the base) = 30mL
Mb (Molarity of the base) = 0.1M
Va (volume of the acid) = 25mL
Ma (Molarity of the acid) =?
The molarity of the acid can be obtained as follow:
MaVa/MbVb = nA/nB
Ma x 25/ 0.1 x 30 = 1
Cross multiply to express in linear form
Ma x 25 = 0.1 x 30
Divide both side by 25
Ma = (0.1 x 30) / 25
Ma = 0.12M
The molarity of the acid is 0.12M
Answer:
Sln
n=m/mr
n=25/100
n=0.25mole of Caco3
Malality =number of moles/volume (divided by number of moles both sides)
volume =Malality /number of moles
v=0.125/0.25
v=0.500L
I hope this help
Answer:
The vapor pressure in solution is 0,0051 atm
Explanation:
This is the formula for vapor pressure lowering, the colligative property.
P vapor = Pressure sv pure . Xsv
Where Xsv is data.
Xsv means Molar fraction (moles solvent/total n° moles)
Vapor pressure of water, pure is 17.5 mmHg
P vapor = 0,0313 atm . 0163
P vapor in solution = 0,0051 atm
Molar fraction does not have units
A solution will have less vapor pressure than that observed in the pure solvent.
