CHEMISTRY A LEVEL WITH SATISFIED SOLUTIONS

CHEMISTRY A LEVEL WITH SATISFIED SOLUTIONS

What are the two elements which are exceptions to the electron configuration? - CORRECT-The two exceptions for this is copper and chromium. In both cases, the 4s subshell contains only one electron, even though there are electrons in the 3d subshell.

To explain this, its because the 3d subshell is more stable when it is either half full, or completely full.

So in the case of chromium, by having only one electron in the 4s subshell, it can have a half-full 3d subshell. It the case of copper, it can have a completely full 3d subshell.

What is the electron configuration of iron? 26,Fe - CORRECT -The electron configuration can be written either in the order of electron shells or the order of filling.

How do you calculate the maximum number of electrons in a given electron shell? - CORRECT -Each shell is given a number, scientists call this the principal quantum number or "n".

Explain how the mass and abundance of the isotopes from mass spectroscopy is identified. - CORRECT -The transfer of electrons from the detector causes a current to flow.

Imagine we have two different isotopes moving down the drift chamber. Since ions of the lighter isotops will have a greater velocity and will reach the drift chamber first. The time taken to move down the drift chamber is used by the machine to determine the mass of the isotope.

The size of the current produced when each isotope hits the detector is used to determine the abundance of each isotope. A more abundant isotope will produce a greater current than a less abundant isotope

The first shell as a principal quantum 1 so

n = 1

The second shell as a principal quantum 2 so n = 2

The third is 3, and the fourth is 4. Etc.

To calculate the maximum number of electron in each shell, you use the equation 2n^2.

e.g.

2(1)^2 = 2

2(2)^2 = 8

2(3)^2 = 18

2(4)^2 = 32

What is meant by an atomic orbital? - CORRECT -An atomic orbital is a region around the nucleus that can hold up to two electrons with opposite spins.

Electrons can either have an up spin or a down spin.

When we have two electrons in the same orbital, these two electrons must have opposite spins. We can't have two electrons with the same spin.

The atomic orbital shows us 95% probability of where an electron will exist, not 100%.

4 different type of orbials and each one has a letter:

s, p, d and f.

Identify the shape of p and s orbitals: - ANSWER-

State the order of orbitals: - ANSWER-1S2 2S2 2P6 3S2 3P6 3D10 4S2 4P6 4D10 4F 14