Answer:

Explanation:
In this case, we have a dilution problem. We have to remember that in the dilution procedure we go from a solution with higher concentration to a solution with lesser concentration. Therefore we have to start with the dilution equation:

Now we can identify the variables:




If we plug all the values into the equation:

And we solve for
:


I hope it helps!
Answer:
0.4 moles
Explanation:
To convert between moles and grams you need the molar mass of the compound. The molar mass of of CaCO3 is 100.09g/mol. You use that as the unit converter.
40gCaCO3* 1mol CaCO3/100.09gCaCO3 = 0.399640 mol CaCO3
This rounds to 0.4 moles CaCO3
I believe it’s A..but I’m not quite sure.
Answer:
The values for spin quantum number +1/2 and - 1/2
Explanation:
Principal quantum number denoted by (n) is used to describe the shell or orbits that electrons are found. Principal quantum number can assume a value of n= 1,2, 3, 4,5............ which indicates K, L, M, N, O shell respectively.
To know the maximum number of electrons in each shell, the formula (2n²) can be used. The letter 'n' denotes the values of principal quantum number 1,2,3,4
For example
- n=1 (K shell) has maximum number of 2 electrons
- n=2 (L shell) has the maximum number of 8 electrons
- n=3 (M shell) has the maximum number of 18 electrons
- n=4 (N shell) has the maximum number of 32 electrons
All the electron in each shell will have a spin quantum number of +1/2 and - 1/2. One electron in each degenerate orbital will spin up (+1/2) while the other electron will spin down (-1/2).