X ray Flashcards
Greek Atom (NAMES)
Leucippus and Democritus
Four fundamental substances: ANCIENT GREEK THEORY
Earth, Water, Air, Fire
• Modified by four essences: ANCIENT
Wet, Dry, Hot, Cold
• Concept of “atom” meaning (?) vice verse
indivisible
• Greek concepts of matter didn’t persist for centuries
T OR F
F, it did persist
Medieval alchemists’ efforts to transform lead into gold were based on these ideas.
ANCIENT GREEK INFLUENCE
T OR F
T
John Dalton’s Contribution (1808)
Proposed elements are composed of identical atoms with unique atomic masses.
• Hook and Eye Affair / Solid Sphere Model
• Example: All oxygen atoms are identical in structure and chemical behavior.
Proposed elements are composed of identical atoms with unique atomic masses.
• Hook and Eye Affair / Solid Sphere Model
• Example: All oxygen atoms are identical in structure and chemical behavior.
NAME AND DATE
John Dalton’s Contribution (1808)
Arranged elements by increasing atomic mass.
• Identified periodic repetition of chemical properties.
• Resulted in the first periodic table with 65 elements
WITH DATE
Dmitri Mendeleev’s Periodic Table (1869)
Dmitri Mendeleev’s Periodic Table (1869)
• Arranged elements by increasing atomic mass.
• Identified periodic repetition of chemical properties.
• Resulted in the first periodic table with 65 elements.
Elements in the same group have similar chemical and physical properties.
• Alkali metals (Group I) react violently with
———
• Halogens (Group VII) form———-
• Noble gases (Group VIII) are ——-
Water
water soluble salts
non reactive
Group 1 of the periodic table, also known as the alkali metals, includes the following elements:
HIGHLY REACTIVE WITH WATER
H(not really)
L
s
p
r
c
f
Lithium
sodium
potassium
rubidium
cesium
francium
Group VII of the periodic table is commonly referred to as Group 17 or the halogens. The elements in this group are:
THEY FORM WATER SOLUBLE SALTS
F
C
B
I
A
T
Fluorine (F)
Chlorine (Cl)
Bromine (Br)
Iodine (I)
Astatine (At)
Tennessine (Ts) - A synthetic element that is not naturally occurring and has only been produced in minute quantities.
Group VIII, also known as Group 18, contains the noble gases. These elements are known for their lack of reactivity due to having a full valence electron shell, making them very stable and inert under most conditions. The noble gases include:
H
N
A
K
X
R
O
Helium (He)
Neon (Ne)
Argon (Ar)
Krypton (Kr)
Xenon (Xe)
Radon (Rn)
Oganesson (Og) - A synthetic element, it is predicted to have properties similar to noble gases, though its reactivity is less well understood.
When was the bohr atom discovered
1913
