Hey there!
1 mole has 6.022 x 10²³ atoms.
Multiply that by 3.2 because we have 3.2 moles.
3.2 x 6.022 x 10²³
1.9 x 10²⁴
There are 1.9 x 10²⁴ atoms in 3.2 moles of chromium.
Hope this helps!
Answer:
i. Atomic radius of an atom is defined as the total distance from the nucleus to the outermost shell of the atom.
On moving from left to right ( Mg, K) in a period, more and more electrons get added up in the same shell and the attraction between the last electron and nucleus increases, which results in the shrinkage of size of an atom. Thus, decreasing the atomic radii of the atom on moving towards right of the periodic table.
As moving from top to bottom, there is an addition of shell around the nucleus and the outermost shell gets far away from the nucleus and hence, the distance between the nucleus and outermost shell increases.
Thus the order of atomic radii is : Ca > Mg > K
ii. The energy required to remove the last valence electron from isolated gaseous atom (first ionization energy) increases as we move from left to right in a period. It decreases on moving from top to bottom.
Thus the order of first ionization energy is : K > Mg > Ca
iii. The chemical properties depend on the valence elctrons and as the elements Mg and Ca both have two valence electrons , they have same chemical properties.
<span> a scientist would do after forming a testable question is </span>test the question.
B. One
I believe that earth is the only planet that has life that we know of on it.
The answer is: <span>The principal idea here is how r they obtained:
for example: sodium u put equal molar concentrations of sodium (Na) and sodium ion (Na+) together in a beaker , then dip in this solution a platinium wire (zero potential) which is connected to a normal hydrogen electrode (electrode with zero potential) then u see the reading of the whole circuit
if it is negtive, this means negative potential which means that the reducing property predominates where Na(reducing agent) is oxidized and electrons r accumulated on the platinum which gives it negative charge
This means that (Na) is a reducing agent, its strength depends on the value of the potential obtained, and here the table can help you
If u want to know if it's strong red. agent, look for it in the table, see if it has higher reduction potentail (or lower oxidation potential, same idea) than most other substances then it is reducing agent
and vice versa
So if we look at ur examples, u will find that MnO4- is the very strong oxidizing agent (has highest oxidation potential) (lowest reduction potential)
H+ and H2 are both with zero potential, no redox properties
And lastly Na and Na+:
This u can know from ur knowledge in chemistry, that sodium is very rarely found in elemental form and always in the form of ion so u can deduce that Na is the very strong reducing agent
or u can see the value of its standard oxi or red potetial and deduce which is the predominating form of them.
I hope this helps</span>