## Midterm Materials [ENDORSED]

Any general non-science questions (software questions/problems, etc.,) and class announcements.

K Stefanescu 2I
Posts: 68
Joined: Fri Sep 29, 2017 7:04 am

### Midterm Materials

Are we to purchase a blue book for the upcoming midterm, or will it be similar to previous exams when all answers were written on the exam?

Belle Calforda3f
Posts: 67
Joined: Fri Sep 29, 2017 7:07 am

### effective nuclear charge

Could someone please explain effective nuclear charge?

Posts: 53
Joined: Fri Sep 29, 2017 7:03 am

### Re: Midterm Materials

Effective nuclear charge deals is the equation: Zeff = z(atomic number) - S(shielding e-). By subtracting these two you will derive the effective nuclear charge

Posts: 53
Joined: Fri Sep 29, 2017 7:03 am

### Re: Midterm Materials

We don't need to buy a blue book for the midterm.

Ryan Sydney Beyer 2B
Posts: 82
Joined: Fri Sep 29, 2017 7:07 am
Been upvoted: 1 time

### Re: Midterm Materials

The definition of effective nuclear charge is the net charge that an electron experiences in an atom with multiple electrons. Basically as the number of electrons increases in an atom, the effective nuclear charge that the outermost electron feels is lowered. The effective nuclear charge can be calculated by the equation::

Zeff = Z - S

Where Z is the atomic number and S is the number of shielding electrons

Electrons with higher energy can have other lower energy electrons between itself and the nucleus which effectively lowers the positive charge experienced by the high energy electron. The shielding effect is related to effective nuclear charge and it is the name given to the balance between valence electrons and protons and the repulsion between valence and inner electrons.

Chem_Mod
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### Re: Midterm Materials  [ENDORSED]

We do not allow blue books on exams but you can still write on the back of each page for scratch work as the exams are one-sided; you should have plenty of room.

Magdalena Palavecino 1A
Posts: 54
Joined: Fri Sep 29, 2017 7:04 am

### Re: Midterm Materials

Should we be able to know the conversion from eV to Joules for the midterm?

Ryan Sydney Beyer 2B
Posts: 82
Joined: Fri Sep 29, 2017 7:07 am
Been upvoted: 1 time

### Re: Midterm Materials

It's going to be given to us on the list of constants and equations so no need to memorize it!