Final Semester 1 Review Flashcards
The chemical formula in a compound indicates:
a. the source of the elements in the compound.
b. how elements are joined int eh compound.
c. the alchemy symbols for the elements in the compound.
d. the relative proportions of the elements in the compound
d.
What happens to matter during a chemical reaction?
matter is neither destroyed or created,
The step that usually comes last in solving numeric problems is…
a. calculate
b. measure
c. evaluate
d. analyze
c. evaluate
A theory is a…
a. proposed explanation for an observation
b. well-tested explanation for a broad set of observations.
c. summary of the results of many observations
d. procedure used to test a proposed explanation
b. a well-tested explanation for a broad set of observations.
An example of an extensive property is…
a. temperature
b. pressure
c. mass
d. hardness
c. mass
how to convert from Celsius to Kelvin
Kelvin = 273 + x Celsius
How many significant figures in:
0.00350
150050
0.00350- 3
150050- 5
What does the number 84 in the name krypton-84 represent?
a. the atomic number
b. the mass number
c. the sum of the protons and electrons
d. twice the number of protons
b. the mass number
All atoms of the same element have the same…
a. number of neutrons
b. number of protons
c. mass numbers
d. mass
b. number of protons
Which of the following is true about subatomic particles?
a. Electrons are negatively charged and are the heaviest subatomic particle.
b. Protons are positively charged and the lightest subatomic particle.
c. Neutrons have no charge and are the lightest subatomic particles.
d. the mass of a neutron nearly equals the mass of a proton.
d. the mass of a neutron nearly equals the mass of a proton.
Which model of the atom is thought to be true today?
a. Protons, electrons, and neutrons are evenly distributed throughout the volume of the atom.
b. The nucleus is made of protons, electrons, and neutrons.
c. Electrons are distributed around the nucleus and occupy almost all the volume of the atom.
d. the nucleus is made of electrons and protons.
c. Electrons are distributed around the nucleus and occupy almost all the volume of the atom.
What charge does and electron have?
A negative charge.
The nucleus is made up of what?
protons and neutrons
What charge does a proton have?
positive charge.
What charge does a neutron have?
no charge. neutral.
What model did JJ Thomson propose?
The Plum Model
How does the energy of an electron change when the electron moves closer to the nucleus?
It decreases
When an electron moves from a lower to a higher energy level, the electron…
a. always doubles its energy
b. absorbs a continuously variable amount of energy
c. absorbs a quantum of energy
d. moves closer to the nucleus.
c. absorbs a quantum of energy
Emission of light from an atom occurs when an electron…
drops from a higher to a lower energy level.
The quantum mechanical model of the atom involves what?
the probability of finding an electron in a certain position.
what information does a molecular formula provide?
the number and kind of atoms present in a molecule
What is the representative unit of a molecular compound?
a molecule
The side-by-side overlap of p orbitals produces what kind of bond?
A pi bond