Answer:
.
Explanation:
Based on the electron configuration of this ion, count the number of electrons in this ion in total:
.
Each electron has a charge of 
.
Atoms are neutral and have 
charge. However, when an atom gains one extra electron, it becomes an ion with a charge of . Likewise, when that ion gains another electron, the charge on this ion would become 
.
The ion in this question has a charge of . In other words, this ion is formed after its corresponding atom gains two extra electrons. This ion has 
electrons in total. Therefore, the atom would have initially contained 
electrons. The atomic number of this atom would be 
.
Refer to a modern copy of the periodic table. The element with an atomic number of is sulphur with atomic symbol 
. To denote the ion, place the charge written backwards ("
" for a charge of ) as the superscript of the atomic symbol:
.
Answer:
0.00316
Explanation:
You have to use the following equation:
![pH=-log[H^+]](https://tex.z-dn.net/?f=pH%3D-log%5BH%5E%2B%5D)
You are given the pH and need to find the concentration of H+. Plug in the given components and solve.
![2.5=-log[H^+]\\H^+ = 10^{-2.5}\\H^+=0.00316](https://tex.z-dn.net/?f=2.5%3D-log%5BH%5E%2B%5D%5C%5CH%5E%2B%20%3D%2010%5E%7B-2.5%7D%5C%5CH%5E%2B%3D0.00316)
The concentration of H is 0.00316.
The answer is (2) release a large amount of energy. Nuclear fission form light nuclides from heavy nuclides. While nuclear fusion form heavy nuclides from light nuclides.
I believe a solution of Sn(NO3)2 can not be stored in an aluminium container because Aluminium is higher in the reactivity series compared to Tin (Sn). Therefore, Aluminium is more reactive than Tin and hence aluminium will displace Tin from its salt forming Aluminium nitrate and Tin metal. Thus storing Tin nitrate in an aluminium container will cause the "eating away' of the container.
