Changes
A type of change where a material becomes a new material with different properties
chemical change
What are the 3 particles that make up an atom?
Proton, neutron, e-
Number of protons in zinc.
30
What are isotopes?
Atoms of an element with different numbers of neutrons.
How many sig figs in 23.0ml?
3
a type of change where a material is changed in some way but is still the same material.
All atoms of carbon have the same number of ____________.
Protons.
Density of iron?
7.87g/ml
The atomic mass shown on the periodic table for any element is considered a ______________ __________________ of the masses of the different isotopes.
weighted average
Convert atomic symbol to element names: B, I, Mn
Boron, Iodine, Manganese.
Provide an example of a chemical change.
burn something, react it with acid, etc.
Atoms of potassium typically have _____ protons and ______ neutrons
19 protons, 20 neutrons
What is the melting point of tin?
505K
Suppose a nucleus of a carbon atom gains an additional proton. Has this created a new isotope of carbon? Explain.
Convert 18400j to scientific notation.
1.84x104j
Provide 2 examples of physical changes
Phase change, break it into pieces, etc.
List the charge, location, and mass of the proton, neutron, and electron.
Proton - positive, nucleus, 1amu
Neutron - neutral, nucleus, 1amu
Electron - negative, orbitals, basically 0amu
What is an atomic symbol?
2 letter abbreviation for an element.
If an element has 2 isotopes with the following mass and abundances, calculate the average atomic mass of the element.
24amu - 34% abundance
25amu - 66% abundance
24.66amu?
The gold foil experiment told Rutherford that...
Atoms are mostly empty space.
List 4 potential signs of a chemical change.
Gas, hot, cold, color, etc.
How do you determine the number of electrons in an atom?
Same as atomic number/number of protons.
Number of neutrons in a typical atom of manganese?
30
Magnesium has 2 different naturally isotopes. One is Mg-24 and the other is Mg-25. Which is more common? Why?
Mg-24, the mass is closer to 24.
How are atomic spectra generated?
Energy is released as photons of light when electronsmove down energy levels.