Question

1. identifie les éléments clés présentés par chaque chimiste à propos de latome

a. dalton
c. rutherford
b. thomson
d. bohr

1. identifie les composants suivant sur le tableau périodique

a. les métaux, les non-métaux, les métalloïdes
b. familles, périodes
c. métaux alcalins, métaux alcalino-terreux, halogènes, gaz nobles, lanthanides, actinides

Explanation:

Identify key atomic model elements

We analyze the key contributions of each chemist to the atomic model:

• Dalton: Billiard ball model; atoms are indivisible spheres.
• Thomson: Plum pudding model; discovered electrons embedded in a positive sphere.
• Rutherford: Nuclear model; discovered the dense positive nucleus via the gold foil experiment.
• Bohr: Planetary model; electrons travel in specific, quantized energy levels (orbits).

Locate metals, non-metals, metalloids

We describe where these three major categories are located on the periodic table:

• Metals: Located on the left side and center of the periodic table (except hydrogen).
• Non-metals: Located on the far right side of the periodic table (plus hydrogen).
• Metalloids: Located along the staircase boundary separating metals and non-metals (B, Si, Ge, As, Sb, Te, Po).

Locate families and periods

We define the orientation of groups and periods:

• Families (Groups): The vertical columns, numbered 1 to 18.
• Periods: The horizontal rows, numbered 1 to 7.

Locate specific chemical families

We identify the locations of the requested chemical families on the periodic table:

• Alkali metals: Group 1 (first column, excluding hydrogen).
• Alkaline earth metals: Group 2 (second column).
• Halogens: Group 17 (second column from the right).
• Noble gases: Group 18 (far-right column).
• Lanthanides: The top row of the bottom detached block (elements 57–71).
• Actinides: The bottom row of the bottom detached block (elements 89–103).

Answer:

Question 2

Identify the key elements presented by each chemist regarding the atom:

• a. Dalton: Proposed that the atom is an indivisible, solid sphere (the "billiard ball" model) and that all atoms of a given element are identical.
• b. Thomson: Discovered the electron and proposed the "plum pudding" model, where negatively charged electrons are embedded in a sphere of positive charge.
• c. Rutherford: Discovered the dense, positively charged nucleus through the gold foil experiment, proposing that electrons orbit around this central nucleus in mostly empty space.
• d. Bohr: Proposed that electrons travel around the nucleus in specific, quantized circular orbits or energy levels.

Question 3

Identify the following components on the periodic table:

• a. Metals, non-metals, metalloids:
• Metals: Located on the left side and in the center of the periodic table (occupying the majority of the table, to the left of the staircase).
• Non-metals: Located on the upper right side of the periodic table (plus Hydrogen on the top left).
• Metalloids: Located along the diagonal "staircase" line that divides metals and non-metals (includes Boron, Silicon, Germanium, Arsenic, Antimony, Tellurium, and Polonium).

• b. Families, Periods:
• Families (Groups): The vertical columns of the periodic table.
• Periods: The horizontal rows of the periodic table.

• c. Specific chemical families:
• Alkali metals: Group 1 (the first vertical column on the far left, excluding Hydrogen).
• Alkaline earth metals: Group 2 (the second vertical column from the left).
• Halogens: Group 17 (the second vertical column from the right).
• Noble gases: Group 18 (the vertical column on the far right).
• Lanthanides: The first (top) horizontal row of the separate block at the bottom of the table.
• Actinides: The second (bottom) horizontal row of the separate block at the bottom of the table.