Hello! The answer is D
A good note for these is when there are three elements, one being a singular element and another a compound and there’s a single switch, this could show a single-displacement
Have a good day gamer.
So that they will mix in better, or more easily. However you want to say it.
I believe it would be better to use an orbital designation than the written configuration, if the number of electrons in the ground state of the atom are quite high for the given element, as above 50, for instance.
This saves space and also one can see the discrete quantized energy levels associated with the subshells of the main energy levels if written in orbital designation.
Given :
Measurements
.
To Find :
The multiplication using significant figures .
Solution :
We know , the least number of significant figures in any number of the problem determines the number of significant figures in the answer.
So , significant figure( S.F) in 4.5 cm is 2 .
S.F in 2000.0 cm is 5 .
S.F in 4 cm is 1 .
So , minimum S.F is 1 .
Therefore , S.F of their product is 1 .
Now , multiplying them we will get :

Now , converting 36000 in 1 significant digit .
First we will write it in exponential 2 S.F form.

Now , to convert 3.6 into 1 S.F we should round off this .
So , round off 3.6 we will get 4 .
Therefore , The multiplication using significant figures is
.
Hence , this is the required solution .
Answer: 
Explanation:
Firstly, we have to find the Molecular mass of potassium oxide (
):
atomic mass: 39 u
atomic mass: 16 u
molecular mass: 
This means that in 1 mole of
there are
and we need to find how many moles there are in
:
1 mole of
-----
of 
-----
of 

This is the quantity of moles in 73.9 g of potassium oxide
Now we can calculate the number of atoms in 73.9 g of potassium oxide by the following relation:

Where:
is the number of atoms in 73.9g of potassium oxide
is the Avogadro's number, which is determined by the number of particles (or atoms) in a mole.
Then:

This is the quantity of atoms in 73.9g of potassium oxide