Topic 7: Periodic Trends, Video A: Atomic Size

Question 1

What are the 3 periodic trends you need to understand and predict from the periodic table?

Answer 1

Atomic/ionic Size

Ionization Energy

Electron Affinity

Question 2

What trend to you see in the atomic number when you cross groups from left to right?

Answer 2

The atomic number of the elements go up.

Question 3

When you go across a period does the group change or the period change?

Answer 3

The group changes.

Question 4

When go across a period from right to left does the atomic numbers of the elements go up or down?

Answer 4

They go down.

Question 5

When you go up or down a group what direction are you going on the periodic table?

Answer 5

You going up or down to the next period.

Question 6

The radius of an atom is defined as what?

Answer 6

Half the distance between the nuclei in a molecule consisting of identical atoms.

Question 7

As you move down a group the atoms generally get bigger or smaller?

Answer 7

Bigger.

Question 8

As you move across a period atoms generally get bigger or smaller?

Answer 8

Smaller.

Question 9

Radii of atoms are measured in what?

Answer 9

Picometers. 10^-12

Question 10

The size of atoms are biggest at what corner of the periodic table?

Answer 10

Bottom left.

Question 11

Atoms are smallest at what corner of the periodic table?

Answer 11

Top right.

Question 12

Opposite charges attract or repel?

Answer 12

Attract.

Question 13

Like charges attract or repel?

Answer 13

Repel.

Question 14

You have 3 positive charges and 1 negative charge and 1 positive charge and 1 negative charge which attraction is greater?

Answer 14

The attraction with the 3 positive and 1 negative charge because there are more positive charges.

Question 15

When the number of electons is the same and there are more protons what happens to the electronic cloud?

Answer 15

There is a shrinking of the electronic cloud because of the increased attraction.

Question 16

When the number of the electrons and protons is the same, the net result is what of the electronic cloud?

Answer 16

A shrinking.

Question 17

The final size of an atom is a balance between the attraction of the electrons to the nucleus and what?

Answer 17

The repulsion of electrons to one another.

Question 18

As you move across a period what happens to the atoms?

Answer 18

The get smaller.

Question 19

As you move down a group what happens to the number of atomic orbital energy levels?

Answer 19

They increase.

Question 20

Atomic size increases or decreases as you move down a group?

Answer 20

Increases because the number of shells increase.

Question 21

As you move across the periodic table atomic size increases or decreases?

Answer 21

Decreases because the proton electron attractions shrink the eletronic cloud.