Laws of chemistry
What does the law of conservation of mass state?
States that mass is neither created nor destroyed during ordinary chemical reactions or physical processes
Neutral atoms contain equal numbers of what two subatomic particles
protons and electrons
What are the relative charges and mass numbers of each subatomic particle?
proton: positive, 1
neutron: neutral, 1
electron: negative, 0
The atomic number always represents what?
the number of protons in an element
The mole is based off of 12.0 g of what element? (be specific)
carbon-12
Law states a chemical compound contains the same elements in exactly the same proportions by mass regardless of the size of the sample or source of the compound
Law of definite proportions
Where are each subatomic particle located?
electrons: electron cloud
protons and neutrons: nucleus
Who discovered the electron
Joseph Thompson
How do you find the neutrons of an atom?
mass number - atomic number
Calculate the number of moles in 4.67 g of Be
0.518 mol Be
The atomic mass of an atom of carbon is 12 amu, and the atomic mass of an atom of oxygen is 16 amu. To produce CO, 16 g of oxygen combine with 12 g of carbon. To produce CO2, 32 g of oxygen combine with 12g of carbon. The ratio of the mass of oxygen in CO2 to the mass of oxygen in CO is.......
2:1
Describe what Dalton's plum pudding model entailed.
Protons and electrons evenly spread throughout the atom
Rutherford
Using a periodic table, what find the following for Barium
1. protons, neutrons, electrons, mass number
56, 81, 56, 137
Calculate the number of atoms in 0.897 mol of Strontium
5.40 x 10^23 atoms Sr
List three of the five components of Dalton's atomic theory.
All matter is composed of atoms
Atoms of an element are identical in size, mass and other properties
Atoms cannot be subdivided, created, or destroyed
Atoms of different elements combine in simple whole-number ratios
In chemical reactions, atoms are combined, separated, or rearranged
The most massive particle in an atom is ______.
neutron
Describe the findings of the cathode ray tube experiment. What subatomic particle was discovered, and how?
answers may vary
Using a periodic table, calculate the following using Al-29.
1. protons, electrons, neutrons, mass number
13, 13, 16, 29
Calculate the number of atoms in 28.0 g of Sulfur
5.26 x 10^23 atoms of Sulfur
What about Dalton's atomic theory was incorrect?
Atoms of an element are identical in size, mass and other properties
Draw the correct atomic model on the board
nucleus in center, with protons and neutrons (positively charged)
electrons surrounding nucleus in cloud
Describe the findings of the gold foil experiment, and what subatomic particle(s) was discovered
answers may vary
Using a periodic table, calculate the following for K+1
1. protons, electrons, neutrons, mass number
19,18,20,39
What is the molar mass of MgCl2?
95.21 g/mol