ATOMIC THEORY
Who was the FIRST person to theorize that matter consisted of atoms? (He also came up with the term "atom")
Democritus
DAILY DOUBLE!
Which 2 subatomic particles have a mass of 1 amu?
Protons
Neutrons
What is the most common isotope of hydrogen in our universe? H - 1 (protium), H - 2 (deuterium), or H - 3 (tritium)?
H - 1 (protium)
6.02 x 1023 atoms of gold (Au) = __ moles?
1 mole
DAILY DOUBLE!
1) what is the name for the counting unit used to count particles?
2) who came up with this counting unit?
1) mole (mol)
2) Avagadro
Atoms of the same element have the same __.
properties
Atomic number ALWAYS tells us the number of what subatomic particle?
protons
What is the % composition of each element (by mass) in an ammonium (NH3) molecule?
82.4% N, 17.6% H
What is the mass of 1 mole of salt (NaCl)?
58 g
What does the word "atom" mean in Greek? (1 word)
indivisible
Atoms cannot be subdivided, __ or __.
created or destroyed
How many protons, neutrons, and electrons are in a fluorine (F) atom?
P = 9
N = 10
E = 9
A mineral in Earth's crust is 25.5% Magnesium (Mg) and 74.5% chlorine (Cl) by mass. What is the formula of this mineral?
MgCl2
7.5 moles of oxygen gas (O2) = ___ g
240 g
DAILY DOUBLE!
How many oxygen (O) atoms are in each compound?
1) C6H12O6
2) Ca(NO3)21) 6
2) 6
compounds
molecules
DAILY DOUBLE!
1) How many protons, neutrons, and electrons are in a barium (Ba+2) ion?
2) What type of ion is Ba+2 ?
1) P = 56 N = 81 E = 54
2) a cation
Bluejayon (Bj) has 2 isotopes in nature. Use the information below to find its average atomic mass:
Bj-123 exact mass = 123.123; 67% abundance
Bj-128 exact mass = 127.987; 33% abundance
(Round your answer to 3 decimal places)
124.728 amu
3.0 x 1050 molecules H2O = __ g
8.97 x 1027 molecules
A substance is 68.4% chromium (Cr) and 31.6% oxygen (O) by mass. What is its empirical formula?
Cr2O3
In __, atoms are combined, separated or rearranged.
reactions
How many protons, neutrons, and electrons are in a carbon - 14 (14C) isotope?
P = 6
N = 8
E = 6
Lithium has 2 isotopes in nature (Li - 6 and Li - 7). Li - 6 has an exact mass of 6.0151223 u and an abundance of 7.5%. What is the exact mass of Li - 7? (Do not round your answer)
7.0160041 u
What is the mass (in grams) of 1 water (H2O) molecule?
2.99 x 10-23 g
0.0000000000000000000000299 g
What is Avagadro's first name?
Amadeo