Unit 8: Atomic Structure & Nuclear
proton
This particle never changes and establishes the atoms identity.
True or False I will do well on the assessment if I take it seriously and prepare.
True
2 days
Use the graph to estimate the half life of the radioactive isotope
What happens to the number of electrons when an Na atom forms a Na(-1) ion? a) they increase by 1 b) they decrease by 1 c) they remain the same
a
number of protons = ________________
atomic number
In an atom with a non-neutral charge, these will be equal in number.
atomic number & # protons
In an element with a neutral charge, these things are all identical in number
atomic number, # of protons, # of electrons
In an atom's symbol, what is located on the bottom left side? a) number of neutrons b) atomic number c) number of electrons
b
Which of the following is true about H - 4 when it is compared to an atom of H - 2? It has.... a) more protons b) more neutrons c) fewer protons d) fewer neutrons
b
Carbon - 13 contains a) 6 protons, 6 neutrons, 6 electrons b) 6 protons, 6 neutrons, 7 electrons c) 6 protons, 7 neutrons, 6 electrons d) 6 protons, 7 neutrons, 7 electrons
c
What happens to the number of protons when an Na atom forms a Na(+1) ion? a) they increase by 1 b) the decrease by 1 c) they remain the same
c
Adding an electron, changes the element's ___________.
charge
Which subatomic particle has the LEAST mass?
electron
When an atom has either a (+) or (-) charge, only the number of these change.
electrons
Increasing the number of protons causes change(s) to the.....
element, atomic mass, charge
An atom has 18 protons, 18 electrons and 22 neutrons. What is its mass number?
forty
The proton is responsible for determining the ______ of an element.
identity
An electron has ....
less mass than a proton or neutron and has a negative charge.
In C - 14, the number fourteen tells us the _______.
mass number
When a neutron is added to an element, the ___________ increases.
mass number
The electron subatomic particle has this type of charge.
negative
What charge does a neutron have?
neutral
Which subatomic particle has a positive charge?
proton
the atomic mass is equal to ....
protons + neutrons
In an atom with a neutral charge, these are all equal in number.
protons, electrons, and atomic number
mass # - # of protons = ________________
the number of neutrons
What subatomic particle determines what the element is?
the proton
What happens to the number of electrons when an Na atom forms a Na(+1) ion? a) they increase by 1 b) they decrease by 1 c) they remain the same
they decrease by 1 (b)
Where is the mass number located in an atom's symbol? a) top left side b) bottom left side c) top right side
top left side (a)
Where is the charge of an ion (a non-neutral atom) located in its symbol? a) top left side b) bottom left side c) top right side
top right side (c)
At atom with an atomic number of 17 and a mass number of 35 has how many neutrons?
18
An atom with a mass number of 39 and an atomic number of 19 has how many neutrons?
20
gamma radiation
A piece of paper would be LEAST effective in protecting against this type of radiation.
alpha radiation
A piece of paper would be MOST effective in protecting against this type of radiation.
25
After 3 half lives there will be ______ Kg of isotope X remaining.
Cl-36
An isotope of Chlorine-39
2
Atomic number of this atom is
loses an electron
How does an atom become a (+) ion?
A new element
If Carbon loses two protons it becomes.
an unstable nucleus
In a nuclear reaction, ____________ changes its number of protons and neutrons, give off large amounts of energy, and increase its stability.
four
Represents the mass number for He
12.5%
The amount of the parent isotope remaining after 3 half lifes
6.25%
The half life of I-131 is 8 days. What fraction or percent of the original sample of this isotope remains after 32 days.
4 days
The half life of isotope "Y" is two days. After how many days is the amount of isotope "Y" 1/4 of its original amount?
2 hours
The half life of isotope X ___________
4
The mass number of this atom is
2 half lifes
The number of half lives that have past when there is 50 Kg of isotope X remaining
atomic number
The number of protons determines this number found on the periodic table.
radioactive decay
The process in which radioactive atoms release energy to get back to a balanced state.
radiation
The release of energy in the form of moving waves or a stream of particles that you cannot see.
half life
The time it takes for half of a radioactive atom to undergo radioactive decay
4 half lives
There will be 6.25% of the parent isotope remaining after ____ half lives
Isotopes
These have the same number of protons and different number of neutrons.
