Molar mass Cu(OH)₂ = <span>97.561 g/mol
1 mol --------- 97.561 g
? mol ---------- 68 g
moles = 68 * 1 / 97.561
moles = 68 / 97.561
= 0.6969 moles
hope this helps!</span>
Answer:
C.) That all matter was composed of earth, fire, water and air
Explanation:
Just took the test
Answer:
Correc option: 
Explanation:
size of atom : it says somthing about how many shell present in a particular atom or ion and it can also be evaluated on the basis of radius of atom.
Br^- and Kr has highest number of shell as compared to other group of species .
Na ,S , Mg ,P all are from 3rd period but Kr and Br^- in the 4th period so size of species of this group will more,
Size increases on increasring the shell number
<h3><u>Answer;</u></h3>
Cations are much smaller than their corresponding parent
<h3><u>Explanation;</u></h3>
- Parent atom has more electrons and thus the effective nuclear charge on each electron is less.
- When a cation is formed electron(s) is/are lost. Thus the effective nuclear charge or simply put, the attraction of the nucleus towards the electrons increases. Therefore, due to greater pull, the nucleus pulls the shells towards it, there by reducing the size, which makes cations smaller than their corresponding parent.
