Hi There! :)
<span>Which elements in the periodic table are metalloids or have semimetallic properties?
</span><span>Boron, Silicon, Germanium, Arsenic, Antimony, and Polonium are all metalloids. Some people consider Astatine a metalloid</span>
Ethanoic (Acetic) acid is a weak acid and do not dissociate fully. Therefore its equilibrium state has to be considered here.

In this case pH value of the solution is necessary to calculate the concentration but it's not given here so pH = 2.88 (looked it up)
pH = 2.88 ==>
![[H^{+}]](https://tex.z-dn.net/?f=%5BH%5E%7B%2B%7D%5D)
=

= 0.001

The change in Concentration Δ
![[CH_{3}COOH]](https://tex.z-dn.net/?f=%5BCH_%7B3%7DCOOH%5D)
= 0.001

CH3COOH H+ CH3COOH
Initial

0 0
Change

-0.001 +0.001 +0.001
Equilibrium

- 0.001 0.001 0.001
Since the

value is so small, the assumption
![[CH_{3}COOH]_{initial} = [CH_{3}COOH]_{equilibrium}](https://tex.z-dn.net/?f=%5BCH_%7B3%7DCOOH%5D_%7Binitial%7D%20%3D%20%5BCH_%7B3%7DCOOH%5D_%7Bequilibrium%7D)
can be made.
![k_{a} = [tex]= 1.8*10^{-5} = \frac{[H^{+}][CH_{3}COO^{-}]}{[CH_{3}COOH]} = \frac{0.001^{2}}{x}](https://tex.z-dn.net/?f=%20k_%7Ba%7D%20%3D%20%5Btex%5D%3D%201.8%2A10%5E%7B-5%7D%20%20%3D%20%20%5Cfrac%7B%5BH%5E%7B%2B%7D%5D%5BCH_%7B3%7DCOO%5E%7B-%7D%5D%7D%7B%5BCH_%7B3%7DCOOH%5D%7D%20%3D%20%20%5Cfrac%7B0.001%5E%7B2%7D%7D%7Bx%7D%20)
Solve for x to get the required concentration.
note: 1.)Since you need the answer in 2SF don&t round up values in the middle of the calculation like I've done here.
2.) The ICE (Initial, Change, Equilibrium) table may come in handy if you are new to problems of this kind
Hope this helps!
Is 2.0 x 10 to the -9th power an option
Co2 will dissolve in water if water is saturated with Co2 first then it will absorb some of CO2 it appear as less is absorb that was actually the case . this would make it appear as present of CACO3 is in original sample is lower than it will be too low
Answer:
0.13 s
Explanation:
We'll begin by converting 24900 mile to metres (m). This can be obtained as follow:
1 mile = 1609.344 m
Therefore,
24900 mile = 24900 mile × 1609.344 m / 1 mile
24900 mile = 4.01×10⁷ m
Finally, we shall determine the time taken for light to circumnavigate the Earth, this can be obtained as follow:
Distance = 4.01×10⁷ m
Speed = 2.998×10⁸ m/s
Time =?
Speed = distance / time
2.998×10⁸ = 4.01×10⁷ / time
Cross multiply
2.998×10⁸ × time = 4.01×10⁷
Divide both side by 2.998×10⁸
Time = 4.01×10⁷ / 2.998×10⁸
Time = 0.13 s
Thus, it will take 0.13 s for light to circumnavigate the Earth.