Answer:
2
Explanation:
You write your answer with the same number of significant figures as the number with the smallest amount of figures, in this case, that number is 2.1 so your answer should be written with 2 significant figures.
Answer:Mixture
Explanation:Doesn’t specify the proportions of the solution so it can’t be a compound, and iron and sulfur are two separate elements.
The correct answer is D. Frequency. I just took the test.
Answer:
Kc = 0.075
Explanation:
The dissociation (α) is the initial quantity that ionized divided by the total dissolved. So, let's calling x the ionized quantity, and M the initial one:
α = x/M
x = M*α
x = 0.354M
For the stoichiometry of the reaction (2:1:1), the concentration of H₂ and I₂ must be half of the acid. So the equilibrium table must be:
2HI(g) ⇄ H₂(g) + I₂(g)
M 0 0 <em> Initial</em>
-0.354M +0.177M +0.177M <em>Reacts</em>
0.646M 0.177M 0.177M <em>Equilibrium</em>
The equilibrium constant Kc is the multiplication of the products' concentrations (elevated by their coefficients) divided by the multiplication of the reactants' concentrations (elevated by their coefficients):
![Kc = \frac{[H2]*[I2]}{[HI]^2}](https://tex.z-dn.net/?f=Kc%20%3D%20%5Cfrac%7B%5BH2%5D%2A%5BI2%5D%7D%7B%5BHI%5D%5E2%7D)
Kc = 0.075
So back in 1665 Robert hook was able to view cells and describe them along with pictures, the reason he was able to see cells was because the microscope was invented a bit before, which allowed him to think about things differently, he was looking at a cork and saw squared objects, these objects were cells, according to him.
So while the cork was the reason he discovers cells on it in the first place,
The microscope was what allowed him to do that
So it’s (HOOKE LOOKING AT A CORK)
And it’s (THE INVENTION OF THE MICROSCOPE)
