Atoms and Elements Flashcards
Define: Matter
anything that takes up space and has mass
What are the building blocks of matter?
atoms
Who coined the word “atomos”?
Leucippus and Democritus
T/F: An atom can be further divided into smaller particles
False, an atom is the smallest unit that CANNOT be divided
What subatomic particle determines the identify of an element?
protons, because the number of protons in an atom is known as its atomic number, which is the defining characteristic of an element
What 2 things are significant of an atom?
- atomic number
- atomic mass
Why is the atomic number and atomic mass significant?
- atomic number tells you number of protons (an e-) in its nucleus, which directly determines its sequence/position on the periodic table
- atomic mass tells you the total number of protons and neutrons in an atom, providing information about the atom’s overall mass
Who discovered the electron? What year did this occur?
J.J. Thomson, 1897
Describe an atom
Atoms are the buidling blocks to matter that is composed of three subatomic particles: protons, neutrons, electrons. Protons and Neutrons and found in the nucleus of an atom, while Electrons revolve around the nucleus.
atoms CANNOT be divided further
Know the charges (+, -, neutral) of a proton, neutron, and electron
Proton: +1 charge
Neutron: no charge
Electron: -1 charge
What are 2 subatomic particles with similar masses?
Protons and Neutrons
Of the three subatomic particles, which is the lightest?
electron
What is the most and least abundant of elements in the earth crust?
Most abundant: Oxygen
Least abundant: Calcium
List elements in order from most to least abundant within the human body
Most abundant
- Oxygen
- Carbon
- Hydrogen
- Nitrogen
- Calcium
Least abundant
CHON, Ca
Trace elements can be found in our body that can be harmful. Name three trace elements
Trace Elements in Human Body:
- Cobalt: heavy metal
- Arsenic: carcinogenic
- Nickel: causes sinus problems
A scientist discovers a new element called abigawhale. The scientist decides to symbolize the element as “AW”. Is this correct? Why/why not?
This is incorrect. The rule when writing symbols for elements is that ONLY the first letter is capitalized. This means it should be written as “Aw”.
An unknown element is given with the numbers: 18 and 200. Which one would be the atomic mass and the atomic number?
Larger number is the atomic mass = 200
Smaller number is the atomic number = 18
What does the atomic number of an element tell you regarding subatomic particles?
Atomic number = #protons (and #electrons in a neutral atom)
What does the atomic mass of an element tell you regarding subatomic particles?
Atomic mass = #protons + #neutrons
Scientists have found that all matter can be broken down chemically into ~100 different elements. Presently, ________ different elements are known. ________ occur naturally, meaning that _________ are synthetic
112 elements are known
88 occur naturally
24 are synthetic (112-88 = 24)
When looking at the periodic table, can an element be a liquid, solid, and/or gas?
Yes, liquid
Yes, solid
Yes, gas
T/F: Because Hydrogen is in Group 1A, it is considered a metal
False, Hydrogen is the only one in Group 1A that is NOT considered a metal; it is a gas
Grab the periodic table of elements that the professor gave us (or refer to Goodnotes). Be able to name Group IA, Group IIA, Group VIIA, Group VIII. Be able to idenitfy which elements are a part of transition metals, inner transition metals, and semimetals/metalloids
Group IA: Alkaline Metals
Group IIA: Alkaline Earth Metals
Group VIIA: Halogens
Group VIIIA: Noble Gasses
Semimetals (Metalloids): Si, Ge, As, Sb, Te, Po
Given the periodic table, know which has characteristics of a metal/nonmetal
To the LEFT of semimetals: characteristics of metals
To the RIGHT of semimetals: characteristics of nonmetals
Sodium (#11) belongs to _______
alkaline metal
Cu (#29) belong to ________
transition metal
O (#8) beings to _________
nonmetals
T/F: Noble gasses (Group VIIIA) have different characteristics/significane compared to Halogens (Group VIIA)
True, because each column of elements have its own characteristics/significance
We look at the _____ to give the characteristic of an atom. It gives it its own significance.
column
Ex: transitional metals have its own characteristics/significance
What is the area used to describe the area where transition metals are found on the periodic table?
the valley
