the first is hydroxide. I believe d is the second one but I'm not 100% positive so you may want to get a second opinion
The one element that is less reactive than the others is Selenium.
Answer:
Concentric circles of contour lines indicate a hilltop; concentric circles with hachure marks indicate a close depression.
Explanation:
Hope this helped Mark BRAINLIEST!!!
Explanation:
It is known that,
Molar mass of Cd = 112.41 g/mol
Standard concentration of Cd = 0.005 mg/L = 
g/L
Hence, we will calculate the molarity as follows.
Molarity = 
= 
M
Equation for the reaction is as follows.
![K_{sp} = [Cd^{2+}][OH^{-}]^{2}]](https://tex.z-dn.net/?f=K_%7Bsp%7D%20%3D%20%5BCd%5E%7B2%2B%7D%5D%5BOH%5E%7B-%7D%5D%5E%7B2%7D%5D)
![2 \times 10^{-34} = 4.45 \times 10^{-8} \times [OH^{-}]^{2}](https://tex.z-dn.net/?f=2%20%5Ctimes%2010%5E%7B-34%7D%20%3D%204.45%20%5Ctimes%2010%5E%7B-8%7D%20%5Ctimes%20%5BOH%5E%7B-%7D%5D%5E%7B2%7D)
![[OH^{-}] = 6.7 \times 10^{-4}](https://tex.z-dn.net/?f=%5BOH%5E%7B-%7D%5D%20%3D%206.7%20%5Ctimes%2010%5E%7B-4%7D)
M
Also,
![[H^{+}] = \frac{10^{-14}}{[OH^{-}]}](https://tex.z-dn.net/?f=%5BH%5E%7B%2B%7D%5D%20%3D%20%5Cfrac%7B10%5E%7B-14%7D%7D%7B%5BOH%5E%7B-%7D%5D%7D)
= 
= 
Relation between pH and concentration of hydrogen ions is as follows.
pH = ![-log [H^{+}]](https://tex.z-dn.net/?f=-log%20%5BH%5E%7B%2B%7D%5D)
= 
= 10.82
Thus, we can conclude that a minimum pH of 10.82 is necessary to reduce the dissolved cadmium ion concentration to the standard.
Elements of the same group show similar chemical properties as they have the same number of valence electrons. Sulfur belongs to the group 16 or 6 A or the oxygen family with 6 valence electrons. The elements of group 6 A are Oxygen, Sulfur, Selenium, Tellurium and Polonium. All of these elements show similar chemical properties. Therefore, when a biochemist studying the properties a sulfur containing biochemical compounds in the body wants to look at any other non-metal with similar properties, he has to consider other elements of the group 6 A like Oxygen (O), Selenium (Se), Tellurium (Te) and Polonium (Po).
