Explanation:
When Henri Becquerel investigated the newly discovered X-rays in 1896, it led to studies of how uranium salts are affected by light. By accident, he discovered that uranium salts spontaneously emit a penetrating radiation that can be registered on a photographic plate.
<span>I would figure this out slowly. So the percentage would be 25 2.6 billion years ago. That would leave it at 50 percent 5.2 billion years ago. If you double that 50 percent to get 100% and double the 5.2 billion years you get 10.4 billion years. This would make the answer, the rock is 10.4 billion years old</span>
Answer:

Explanation:
Hello,
In this case, for the given reaction at equilibrium:

We can write the law of mass action as:
![Keq=\frac{[CH_3OH]}{[CO][H_2]^2}](https://tex.z-dn.net/?f=Keq%3D%5Cfrac%7B%5BCH_3OH%5D%7D%7B%5BCO%5D%5BH_2%5D%5E2%7D)
That in terms of the change
due to the reaction extent we can write:
![Keq=\frac{x}{([CO]_0-x)([H_2]_0-2x)^2}](https://tex.z-dn.net/?f=Keq%3D%5Cfrac%7Bx%7D%7B%28%5BCO%5D_0-x%29%28%5BH_2%5D_0-2x%29%5E2%7D)
Nevertheless, for the carbon monoxide, we can directly compute
as shown below:
![[CO]_0=\frac{0.45mol}{1.00L}=0.45M\\](https://tex.z-dn.net/?f=%5BCO%5D_0%3D%5Cfrac%7B0.45mol%7D%7B1.00L%7D%3D0.45M%5C%5C)
![[H_2]_0=\frac{0.57mol}{1.00L}=0.57M\\](https://tex.z-dn.net/?f=%5BH_2%5D_0%3D%5Cfrac%7B0.57mol%7D%7B1.00L%7D%3D0.57M%5C%5C)
![[CO]_{eq}=\frac{0.28mol}{1.00L}=0.28M\\](https://tex.z-dn.net/?f=%5BCO%5D_%7Beq%7D%3D%5Cfrac%7B0.28mol%7D%7B1.00L%7D%3D0.28M%5C%5C)
![x=[CO]_0-[CO]_{eq}=0.45M-0.28M=0.17M](https://tex.z-dn.net/?f=x%3D%5BCO%5D_0-%5BCO%5D_%7Beq%7D%3D0.45M-0.28M%3D0.17M)
Finally, we can compute the equilibrium constant:

Best regards.
Answer:
The mass of a solute divided by the mass of a solution times 100
Explanation:
The concentration of a solution refers to how much of a solute is dissolved in an amount of solvent. To express this concentration exist different methods, the mass percent concentration is one of them and is <em>defined as the mass of a solute divided by the mass of a solution times 100:</em>
<em>%m/m= (mass of a solute/mass of solution)x100</em>
<em>Where the mass of the solution is the sum of the mass of solute and mass of solvent.</em>
%m/m is commonly used when you can measure the masses of both solute and solution.
I hope you find this information useful and interesting! Good luck!
<u>The answer is </u><u>9.94 ml.</u>
<h3>
What is density?</h3>
- Density is a word we use to describe how much space an object or substance takes up (its volume) in relation to the amount of matter in that object or substance (its mass).
- Another way to put it is that density is the amount of mass per unit of volume. If an object is heavy and compact, it has a high density.
Given,
The density of ethanol, C2H5OH = 0.789 g/mL


= 7.843 g

Therefore, the answer is 9.94 ml
Learn more about density of ethanol,
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<u>The complete question is -</u>
If the density of ethanol, C2H5OH, is 0.789 g/mL. How many milliliters of ethanol are needed to produce 15.0 g of CO2 according to the following chemical equation?
C2H5OH(l) + 3 O2(g) → 2 CO2(g) + 3 H2O(l)