Answer:
sun gives you vitamin D
Explanation:
Our body creates vitamin D from direct sunlight on our skin when we're outdoors.
Answer:
The percent ionization is 0,16%
Explanation:
The percent ionization is defined as the number of ions that exist in a substance.
![PI=\frac{[A-]}{[HA]} x100](https://tex.z-dn.net/?f=PI%3D%5Cfrac%7B%5BA-%5D%7D%7B%5BHA%5D%7D%20x100)
First, we find the [A-] using the ka equation
HA ⇄ 
[H+] = [A-]
![Ka=\frac{[H+][A-]}{[HA]}\\ \\](https://tex.z-dn.net/?f=Ka%3D%5Cfrac%7B%5BH%2B%5D%5BA-%5D%7D%7B%5BHA%5D%7D%5C%5C%20%5C%5C)
since the ionization constant is very small we can assume that the final concentration of [HA] is the same
![Ka=\frac{[H+]^{2} }{[HA]} \\\\](https://tex.z-dn.net/?f=Ka%3D%5Cfrac%7B%5BH%2B%5D%5E%7B2%7D%20%7D%7B%5BHA%5D%7D%20%5C%5C%5C%5C)
![[H+]=\sqrt[2]{Ka.[HA]} \\\\](https://tex.z-dn.net/?f=%5BH%2B%5D%3D%5Csqrt%5B2%5D%7BKa.%5BHA%5D%7D%20%5C%5C%5C%5C)
![[H+] =\sqrt{(2,610^{-7} )(0,1)} = 1,61210^{-4}](https://tex.z-dn.net/?f=%5BH%2B%5D%20%3D%5Csqrt%7B%282%2C610%5E%7B-7%7D%20%29%280%2C1%29%7D%20%20%3D%201%2C61210%5E%7B-4%7D)
Now we calculate the percent ionization using these values
PI=0,16%
Answer:
Maybe try to memorize it by the valence electrons. You can do this!!
Answer:
Boron family.
Explanation:
Group 13 is called boron family.
It consist of five members boron, aluminum, gallium, indium and thallium.
Boron is semi metal while other members are metals.
Boron hydrates are used to make organic compounds.
Al is soft metal and aluminum oxides are widely used as thermal insulator.
Aluminum sulfate is also very important commercial compound used in sizing paper.
Gallium is also very important element of this group. It form gallium arsenide which is used to convert the light into electricity.
Indium is malleable soft metal which is used in optical instruments.
Thallium is highly toxic and for the long period of time it as used as insect killing poison.
