All About the Atom
Which subatomic particle(s) (i.e. proton, neutron, electron) contribute to mass number?
proton and neutron
In a Lewis Dot model, what do the dots represent? Be specific.
Valence electrons
Matter is anything that has _______ and _________
mass and volume (occupies space)
What IMF is found in all molecules, regardless of polarity?
London Dispersion
How many sig figs are in the following number?
02.08 x 10^5
3
Isotopes of the same element have the same number of ______________, but different numbers of ________________.
same # of protons, different # of neutrons
Ionic bonds are formed when which two types of elements transfer electrons?
Metal and nonmetal
At what temperature do all particles stop moving?
ZERO kelvin/ABSOLUTE ZERO
In a phase change diagram, are the 3 phases (S, L, G) represented by the diagonal lines or the horizontal lines?
diagonal lines
What are the 7 diatomic elements?
H O N Cl Br I F
How many electrons does a Na+ ion have if it has an atomic number of 11?
10 electrons
11 protons (+1) -10 electrons (-1) = +1
How many lone pairs are there in total in a molecule of oxygen (O2)?
4 lone pairs (total of 8 electrons)
What is average kinetic energy?
Temperature, average energy of motion of particles in a substance
Which IMF is responsible for the attractions between Na+, Cl- ions and H2O (water) in solution?
Ion-dipole
The phrase "Like dissolves like" refers to what?
Substances of similar polarity are soluble together.
Nonpolar dissolves nonpolar
Polar dissolves polar
Shielding refers to the inner-shell (core) electrons repelling outer valence electrons, which lowers the nuclear pull experienced by outer electrons. How does shielding change with increasing atomic size?
It increases. As the atom gets larger, there are more inner-shell electrons, therefore more shielding.
The modern Electron Cloud model has been accepted as a more accurate representation of the atom than the Bohr model due to its inaccuracies. Which of the four electron principles does the Bohr model violate?
Heisenberg Uncertainty Principle.
Compounds (such as NaCl, and MgCl2, and H2O) are classified as what type of matter?
(Think of the matter classification diagram)
Pure substances
Give 3 examples of molecules that have Hydrogen-bonding as one of their IMFs
NH3, H2O, HF
What is Coulomb's law?
like charges repel. opposite charges attract
Extra 50pts: if mentioned, magnitude of attraction/repulsion is dependent on distance between and the size of the charges.
How many principal energy levels does Calcium have? If you need to, draw the Bohr model for calcium.
4 principal energy levels/electron shells
2-8-8-2
Elements in the same __________ have similar chemical properties because they have same number of ____________________
group/column
valence electrons
What distinguishes a molecule from a compound? Give an example of each.
Molecules are two or more atoms *covalently* bonded together. They can be of the same or different elements. Compounds are two or more atoms of *different elements* bonded together. They can be ionic or covalent.
What increases the strength of LDF in nonpolar molecules?
increasing size/# of electrons
In isotope notation, the element symbol is listed on the right. Which number goes in the top left corner and which number goes in the bottom left corner?
top left: mass number
bottom left: atomic number/number of protons