Answer:
97200yrs,
Explanation:
Given parameters:
Half-life of Plutonium - 239 = 24300yrs
Mass of the isotope = 8kg
Unknown:
Number of years it will take for the amount to reduce to 1kg = ?
Solution:
The half -life of any substance is the time taken for half of the compound to decay to half its original composition.
<em> Start first half life second half life third half life</em>
mass 8kg 4kg 2kg 1kg
Time 0yrs 24300 48600 97200
By 97200yrs, the mass would have been 1kg
Answer:
Explanation:
To convert from moles to particles, we must Avogadro's Number.
This number tells us the number of particles (atoms, ions, molecules, etc.) in 1 mole of a substance. In this case, it is the particles of calcium in 1 mole of calcium.
We can use Avogadro's Number as a ratio or fraction.
Multiply this by the given number of particles (3.57*10³²).
Flip the fraction so the particles of calcium will cancel out.
There are <u>592,826,303.6 moles</u> of calcium in 3.57*10³² particles of calcium.
Answer:
Catabolic reactions
Explanation:
Anabolic reactions combine monosaccharides to form polysaccharides, fatty acids to form triglycerides, amino acids to form proteins, and nucleotides to form nucleic acids. These processes require energy in the form of ATP molecules generated by catabolic reactions.
Answer:
2.05 liters
Calculate the molar mass of Ca(OH)2 =74.09g/mol
Calculate how many mol of Ca(OH) are in 64g
n=m/MM
n=64/74.09
n=0.86 mol
Calculate the volume of solution
M=n/V => V=n/M
V= 0.86 mol/ 0.420M
V= 2.05 liters
Ka for weak acids is ---> Ka= (X)²/ (initial- X)
initial= 0.0400 M
to find X, you can find the H concentration using pH
[H+]= 10^-pH
[H+]= 10^-1.80= 0.016 which is X
ka = (0.016)²/ (0.0400 - 0.016) = 0.011
