Atoms and the periodic table

Question 1

What are atoms?

Answer 1

Basic units of elements, consisting of protons, neutrons, and electrons.

Question 2

Define elements.

Answer 2

Pure substances made up of only one type of atom.

Question 3

What are compounds?

Answer 3

Substances formed from two or more elements chemically bonded together.

Question 4

List the four historical atomic models.

Answer 4

• Dalton’s solid sphere model
• Thomson’s plum pudding model
• Rutherford’s nuclear model
• Bohr’s planetary model

Question 5

What is the current model of atomic structure?

Answer 5

Quantum mechanical model.

Question 6

What charge do protons carry?

Answer 6

Positively charged.

Question 7

What are neutrons?

Answer 7

Neutral particles located in the nucleus.

Question 8

What charge do electrons carry?

Answer 8

Negatively charged.

Question 9

How small are atoms typically?

Answer 9

Around 0.1 nanometers in diameter.

Question 10

Where is most of an atom’s mass concentrated?

Answer 10

In the nucleus, composed of protons and neutrons.

Question 11

Define relative atomic mass.

Answer 11

The weighted average mass of an atom of an element compared to 1/12th the mass of a carbon-12 atom.

Question 12

What are isotopes?

Answer 12

Atoms of the same element with the same number of protons but different numbers of neutrons.

Question 13

What does electronic structure refer to?

Answer 13

The arrangement of electrons in energy levels or shells around the nucleus.

Question 14

How was the periodic table initially arranged?

Answer 14

By atomic mass.

Question 15

How is the modern periodic table organized?

Answer 15

By atomic number.

Question 16

Where are metals typically found in the periodic table?

Answer 16

On the left and center.

Question 17

What are the characteristics of metals?

Answer 17

• Shiny
• Malleable
• Ductile
• Good conductors of heat and electricity

Question 18

Where are non-metals located in the periodic table?

Answer 18

On the right side.

Question 19

What are the characteristics of non-metals?

Answer 19

• Dull
• Brittle
• Poor conductors of heat and electricity

Question 20

Define groups in the periodic table.

Answer 20

Vertical columns (1-18) where elements have similar chemical properties.

Question 21

What are periods in the periodic table?

Answer 21

Horizontal rows (1-7) where elements transition from metallic to non-metallic properties.

Question 22

Describe Group 0 elements.

Answer 22

Noble gases that are inert, colorless, odorless, and have full valence electron shells.

Question 23

List the elements in Group 0.

Answer 23

• Helium (He)
• Neon (Ne)
• Argon (Ar)
• Krypton (Kr)
• Xenon (Xe)
• Radon (Rn)

Question 24

What are the characteristics of Group 1 elements?

Answer 24

Soft, shiny metals that are highly reactive, especially with water.

Question 25

List the elements in Group 1.

Answer 25

* Lithium (Li) * Sodium (Na) * Potassium (K) * Rubidium (Rb) * Cesium (Cs) * Francium (Fr)

Question 26

What trends are observed in Group 1?

Answer 26

* Increasing reactivity down the group * Decreasing melting and boiling points * Lower densities

Question 27

Describe Group 7 elements.

Answer 27

Diatomic, non-metallic elements that are highly reactive.

Question 28

List the elements in Group 7.

Answer 28

* Fluorine (F₂) * Chlorine (Cl₂) * Bromine (Br₂) * Iodine (I₂) * Astatine (At₂)

Question 29

What trends are observed in Group 7?

Answer 29

* Decreasing reactivity down the group * Changes from gases to solids at room temperature

Question 30

What are the characteristics of transition metals?

Answer 30

Elements known for their ability to form various oxidation states and good conductivity.

Question 31

List examples of transition metals.

Answer 31

* Iron (Fe) * Copper (Cu) * Gold (Au)