Answer:
9.4
Explanation:
The equation for the reaction can be represented as:
+ 
⇄ 
The ICE table can be represented as:
+ 
⇄
Initial 0.27 0.49 0.0
Change -x -2x x
Equilibrium 0.27 - x 0.49 -2x x
We can now say that the concentration of at equilibrium is x;
Let's not forget that at equilibrium = 0.11 M
So:
x = [] = 0.11 M
[] = 0.27 - x
[] = 0.27 - 0.11
[] = 0.16 M
[] = (0.49 - 2x)
[] = (0.49 - 2(0.11))
[] = 0.49 - 0.22
[] = 0.27 M
![K_C = \frac{[CH_3OH]}{[CO][H_2]^2}](https://tex.z-dn.net/?f=K_C%20%3D%20%5Cfrac%7B%5BCH_3OH%5D%7D%7B%5BCO%5D%5BH_2%5D%5E2%7D)
= 9.4
∴ The equilibrium constant at that temperature = 9.4
Ionization/dissociation, Ka, larger, concentration/molarity, mostly/completely, strong, weak, base, water, acid, strong
To solve this question, we first need to know the mass of one mole of mercury. This can be done by checking the periodic table.
From the periodic table, we can see that:
molar mass of mercury = 200.59 grams/mole.
From the measurements, the chemist found that the participated amount of mercury is 0.02 moles.
We can simply determine the mass of 0.02 moles by doing cross multiplication as follows:
mass of 0.02 moles = (0.02 x 200.59) / 1 = 4.0118 grams
Rounding the answer to 2 significant digits, we get:
mass of 0.02 moles = 4.01 grams
Answer:
B. The student should model a convex lens because it directs light toward the center of the lens.
Explanation:
Lenses are optical devices that work on the principle of refraction.
Refraction is a phenomenon of wave (such as light waves) that occurs when a ray of light crosses the interface between two mediums with different optical density: when this occurs, the ray of light bends and change speed.
In particular, there are two types of lenses:
- Convex lenses: these lenses are curved outward at their center, therefore the rays of light coming from infinite distance (parallel to the axis) are all focused into a point of the lens, called principal focus. Therefore, a convex lens directs lights towards this point.
- Concave lenses: these lenses are curved inward at their center, therefore the rays of light coming from infinite distance are bent away from the principal focus. Therefore, this is a diverging lens, as the rays of light do not converge.
So, the correct answer is
B. The student should model a convex lens because it directs light toward the center of the lens.
