Answer:
Group 1 (or IA)
Explanation:
If element X is a halogen, then it belongs to the group 17 (or VIIA, under a different notation).
For each extra unit of atomic number, the group number increases by 1. That means that the X+1 element would belong to the group 18 (or VIIIA). <em>The X+2 element would thus belong in the group 1 </em>(or IA) one period higher (higher as in numeric value, not as in position in the periodic table).
Answer: a) pH = 13.00 : basic
b)
: basic
c) pOH = 5.00 : basic
d)
: acidic
Explanation:
pH or pOH is the measure of acidity or alkalinity of a solution.
pH is calculated by taking negative logarithm of hydrogen ion concentration.
![pH=-\log [H_3O^+]](https://tex.z-dn.net/?f=pH%3D-%5Clog%20%5BH_3O%5E%2B%5D)
Acids have pH ranging from 1 to 6.9 and bases have pH ranging from 7.1 to 14.Neutral substances have pH of 7.
a) pH = 13.00
As pH is more than 7, the solution is basic.
b) ![[H_3O^+]=1.0\times 10^{-12}](https://tex.z-dn.net/?f=%5BH_3O%5E%2B%5D%3D1.0%5Ctimes%2010%5E%7B-12%7D)
Putting in the values:
![pH=-\log[1.0\times 10^{-12}]](https://tex.z-dn.net/?f=pH%3D-%5Clog%5B1.0%5Ctimes%2010%5E%7B-12%7D%5D)

As pH is more than 7, the solution is basic.
c) pOH = 5.00


As pH is more than 7, the solution is basic.
d) ![[OH^-]=1.0\times 10^{-9}](https://tex.z-dn.net/?f=%5BOH%5E-%5D%3D1.0%5Ctimes%2010%5E%7B-9%7D)
Putting in the values:
![pOH=-\log[1.0\times 10^{-9}]](https://tex.z-dn.net/?f=pOH%3D-%5Clog%5B1.0%5Ctimes%2010%5E%7B-9%7D%5D)



As pH is less than 7, the solution is acidic.
Answer: The gas phase is unique among the three states of matter in that there are some simple models we can use to predict the physical behavior of all gases—independent of their identities. We cannot do this for the solid and liquid states. ... Gas particles do not experience any force of attraction or repulsion with each other.
Explanation: