midterm 4 Flashcards
What was so important about the Gold foil experiment?
proved Thomson’s plum pudding model was wrong. That the atom has nucleus. Most of an atom is empty space.
There are several models of the atom in Chapter 14. You should study them and differentiate them.
Rutherford Model-Solar System.
Bohr Model
Plum Pudding Model
You should know why hydrogen has a discrete spectrum of light and what model of the atom explains it.
Hydrogen only has one visible spectrum of light while the rest are Ultraviolet and infrared regions.
It has a Discrete spectra.It looks red and when passed through a prism, only four colors are found. The red color we see if a result of those for colors combined.
How does atomic volume affect chemical reactivity?
the bigger the atomic volume, the more reactive the atom will be.
How does ionization energy affect chemical reactivity?
the smaller the ionization energy, the more reactive the atom will be.
What family of elements is the most reactive?
alkaline metals (Group 1)
Biggest atomic value
smallest ionization energy
What family of elements is the least reactive?
Noble gasses (Group 8) smallest atomic value, highest ionization energy
What family of elements is the most reactive?
alkali metals (Group 1)
Biggest atomic value
smallest ionization energy
If you were to look at the periodic table of the elements how would you group the families?
metals and non-metals
What distinguishes one atom from another atom?
All elements have different protons and atoms in their form
atomic number
Who came up with the first periodic table of the elements?
Dmitri Mendeleev
What is an isotope?
One of two or more atoms that have the same atomic number (the same number of protons) but a different number of neutrons
Where are metals, non-metals, semimetals or metalloids, and transition metals on the periodic table of the elements?
left: metals
middle: transition metals
stairs: semi metals
stairs above: nonmetals
What does the atomic mass tell you about the element?
sum of protons and neutrons in an atom
What do the groups/families in the periodic table have in common?
similar properties
Elements on the periodic table are ordered according to their ____________
physical and chemical properties change systematically from element to element
What does the atomic number mean?
atomic number is protons
If you study sections 18-1 and 18-2 then there is one sentence that you could use to describe the two sections.
order to disorder.
if total disorder is increased, the process is irreversible.
Irreversible go forward, reversible can go backward at same time.
In the introduction of chapter 18 the idea of quantity and quality of energy is discussed. What happens to the quantity and quality of energy in an energy transfer process?
quantity of energy may be conserved in a transformation, the quality of the energy is generally degraded.
reversible, irreversible
a reversible process does not change the total amount of disorder in the universe.
an irreversible process increases the total amount of disorder in the universe.
Study Section 18-4. There will be a question from that section. Don’t worry about memorizing the whole list. Just know what type of energy is the most and least ordered.
most to least
- gravitational PE and macroscopic KE
- nuclear PE
- Electrical(household)
- Chemical PE
- Thermal Energy (heat, microscopic energy)
Study atomic matter, molecular matter, and network matter from section 19-2. There will be three questions on the test related to those three subjects.
Atomic matter- matter that exists in any states as single atoms
Molecular matter-matter that exists as molecules in any state
network matter-substances in which every atom or ion interacts strongly with many neighbors to form a continuos linked network
There will be a question based on figuring out the pattern for hydrocarbons. Study methane, ethane, propane … what is the pattern between the number of carbon atoms and the number of hydrogen atoms.
single bond C, add on H
reaction process
PE surface, activation energy required to form the transition state–catalyst lowers energy and/or increases the entropy to transition state, energy release (bond formation), , net energy change for reaction, products
There will be a question on balancing chemical equations section 20-3
math to make the addition equal the sum
What is a catalyst?
chemicals that speed up reactions without being consumed themselves.
they make the energy and/or entropy of the transition state more favorable without affecting the energies or entropies of the initial or final products.
why is a spark required to ignite a propane gas stove?
it is an activation energy. sometimes the kinetic energy of colliding molecules is not enough so it requires spark
Bohr Model of the Atom
electrons move around the nucleus in circular orbits. Fist orbit is larger than nucleus. as quantum number increases the energy and radius of orbit increase.
