LSUA Physical Science 1001 Test 1
The dog is smelling molecules from the cat.
A cat strolls across your backyard. An hour later, a dog with its nose to the ground follows the trail of the cat. Explain what is going on from a molecular point of view.
growth of a tree
An example of a chemical change is the:
formation of a cloud
An example of a physical change is the:
scientific research that seeks to solve practical problems
Applied Research:
Metallic
Are most elements metallic or nonmetallic?
weighted average of the mass of various isotopes of an element (number of protons + number of neutrons)
Atomic Mass
number of protons in nucleus, which is what determines which element the atom is
Atomic Number
One electron can be boosted to many different energy levels.
How can a hydrogen atom, which has only one electron, have so many spectral lines?
There are many possible combinations of atoms.
How do we account for the great variety of substances in the world?
superscript mass number (number of protons + number of neutrons); subscript number of protons; atomic symbol
How do you write isotope notation?
When an electron wave is confined, it is reinforced only at particular frequencies.
How does the wave model of electrons orbiting the nucleus account for the fact that the electrons can have only discrete energy values?
About 2 million m/s
How fast does an electron move within an atom?
7
How many atoms are in one molecule of Na2SO4?
5
How many atoms of Oxygen (O) are in H3OClO4
3
How many different elements are in the compound C6H12O6?
12/6 C
If two protons and two neutrons are removed from the nucleus of an oxygen-16 atom, a nucleus of which element remains?
Sodium chloride has nothing in common with sodium and chlorine
If you eat metallic sodium or inhale chlorine gas, you stand a strong chance of dying. Let these two elements react with each other, however, and you can safely sprinkle the compound on your popcorn for better taste. What is going on?
We are continually exchanging our atoms.
In what sense can you truthfully say that you are a part of every person around you?
microscopic
Is a biological cell macroscopic, microscopic, or submicroscopic?
no
Is it possible to see an atom using visible light?
chemical change because the atoms are connected differently
Is the following transformation representative of a physical or a chemical change?
no charge, located in the nucleus, approximately the same mass as a proton
Properties of a neutron:
approximately the same mass as a neutron, +1 charge, located in the nucleus
Properties of a proton:
orbits the nucleus, -1 charge, smallest mass of the three particles, no substantial weight
Properties of an electron:
scientific research driven by curiosity to answer a basic question
Pure Research:
water molecule, virus, bacterium
Rank the following in order of increasing volume: bacterium, virus, water molecule
electron, proton, neutron
Rank the three subatomic particles in order of increasing mass:
The electrons on the atoms repel other electrons on other atoms when they get close.
Since atoms are mostly empty space, why don't objects pass through one another?
macroscopic
The amount of water in a swimming pool is:
have existed since the start of the universe, though new atoms are made inside of stars
The atoms that make your body:
alkali metals; very reactive
The column on the far left of the Periodic Table:
noble gases; not very reactive at all
The column on the far right of the Periodic Table:
halogens; very reactive
The column one over from the far right of the Periodic Table:
halogens
The elements fluorine, chlorine, and bromine are also known as:
amu
The unit for approximate atomic mass:
as you move from top to bottom down a group, atomic radius increases
Trends of atomic radius in groups:
as you move left to right across a period, atomic radius decreases
Trends of atomic radius in periods:
the number of valence electrons increases within a period from left to right for the main group elements
Trends of valence electrons in Periodic Table:
a physical change
Water and ethanol can be separated by heating the ethanol until it boils away from the water. What type of change is this?
atoms
What are molecules made of?
Their outermost occupied shells are filled to capacity.
What do the electron configurations for all the group 18 noble gases have in common?
nucleus
What is at the center of every atom?
Co
What is the atomic symbol for the element Cobalt?
Energy comes in discrete packets of a certain minimum size.
What is the main tenet of Plank's quantum hypothesis?
Electrons could only move in discrete energy steps within an atom.
What was Niels Bohr's explanation for the observation of atomic spectra?
indirectly
When we use a scanning probe microscope, do we see atoms directly to indirectly?
More atoms in carbon-12 because each atom weighs a little less in carbon-12, therefore you need more atoms of carbon-12 to make a gram.
Which as more atoms: a 1-g sample of carbon-12 or a 1-g sample of carbon-13?
protons
Which contributes more to an atom's mass: electrons or protons?
electrons
Which contributes more to an atom's size?
the air you breathe out
Which has more mass, the air you breathe in or the air you breathe out?
an electron far from the nucleus
Which has more potential energy: an electron close to the nucleus or an electron far from the nucleus?
They are of the same age, which is appreciably older than the solar system.
Which is older, the atoms in the body of an elderly person or those in the body of a baby?
Biology because it is based upon both the laws of chemistry and physics.
Which is the most complex science?
1 g of water vapor
Which occupies the greatest volume: 1 g of ice, 1 g of liquid water, or 1 g of water vapor?
the last one
Which of the following diagrams best represents the size of the atomic nucleus relative to the size of the atom?
molecules move faster and more spread apart
With the addition of heat:
