To solve this problem, let us first calculate for the rate
constant k using the half life formula:
t1/2 = ln 2 / k
where t1/2 = half life period = 24,000 years, therefore k
is:
k = ln 2 / 24,000
k = 2.89 x 10^-5 / yr
Now we use the rate equation:
A = Ao e^(-k t)
where,
A = mass of Plutonium-239 after number of years
Ao = initial mass of Plutonium-239
t = number of years
A. t = 12,000 years, find A
A = 100g e^(- 2.89 x 10^-5 * 12,000)
A = 70.7 g
B. t = 24,000 years, find A
A = 100g e^(- 2.89 x 10^-5 * 24,000)
A = 50 g
C. t = 96,000 years, find A
A = 100g e^(- 2.89 x 10^-5 * 96,000)
<span>A = 6.24 g</span>
Answer:
2.05*10⁻⁵ moles of CF₂ can dissolve in 100 g of water.
12.82 moles of CaF₂ will dissolve in exactly 1.00 L of solution
Explanation:
First, by definition of solubility, in 100 g of water there are 0.0016 g of CaF₂. So, to know how many moles are 0.0016 g, you must know the molar mass of the compound. For that you know:
- Ca: 40 g/mole
- F: 19 g/mole
So the molar mass of CaF₂ is:
CaF₂= 40 g/mole + 2*19 g/mole= 78 g/mole
Now you can apply the following rule of three: if there are 78 grams of CaF₂ in 1 mole, in 0.0016 grams of the compound how many moles are there?
moles=2.05*10⁻⁵
<u><em>2.05*10⁻⁵ moles of CF₂ can dissolve in 100 g of water.</em></u>
Now, to answer the following question, you can apply the following rule of three: if by definition of density in 1 mL there is 1 g of CaF₂, in 1000 mL (where 1L = 1000mL) how much mass of the compound is there?
mass of CaF₂= 1000 g
Now you can apply the following rule of three: if there are 78 grams of CaF₂ in 1 mole, in 1000 grams of the compound how many moles are there?
moles=12.82
<u><em>12.82 moles of CaF₂ will dissolve in exactly 1.00 L of solution</em></u>
The standard state formation reaction is a chemical reaction in which one moles of substance in its standard state is formed from its constituent element in their standard state.All the substance must be in their most stable state at 100kpa and 25 degrees celsius.
therefore for HF is
1/2H2 +1/2F2 =HF
As we have the balanced reaction equation is:
N2O4 (g) ↔ 2NO2(g)
from this balanced equation, we can get the equilibrium constant expression
KC = [NO2]^2[N2O4]^1
from this expression, we can see that [NO2 ] is with 2 exponent of the stoichiometric and we can see that from the balanced equation as NO2
is 2NO2 in the balanced equation.
and [N2O4] is with 1 exponent of the stoichiometric and we can see that from the balanced equation as N2O4 is 1 N2O4 in the balanced equation.
∴ the correct exponent for N2O4 in the equilibrium constant expression is 1
Answer:
magnitude means absolute value, so the one that is greastest, like |-7| and |4| even id |-7| is a negative number, but it is still the one farthest away from 0, so |-7| is greater than |4|.
That is the way to find the greatest magnitude, but because I don't know your numbers so I can not answer your question, but this is the way to solve for it.
HOPE THIS HELPS!!!!!!!!!( IF IT DOES <u><em>PLEASE MARK ME AS BRAINLIEST )</em></u>
