Matter Mayhem
This is the term for a pure substance made of only one type of atom.
an element
This scientist proposed a 'planetary model' of the atom with electrons orbiting a nucleus.
Niels Bohr
This type of electromagnetic wave has the longest wavelength on the spectrum.
Radio waves
Elements in the same column of the periodic table are called this.
Groups or family
In nuclear fission, one heavy nucleus splits into two or more smaller nuclei, releasing what type of energy?
Nuclear energy
Matter that has a definite volume but no definite shape is in this state.
liquid
The number of protons in an atom's nucleus determines this.
The atomic number
T/F: Microwaves are harmful to humans (Write just the letter)
False
This periodic trend describes the attraction the nucleus has for the outermost electrons.
The time it takes for half of a radioactive sample to decay is called this.
Half-life
A homogeneous mixture where one substance is dissolved in another is called this.
a solution
Atoms of the same element with different numbers of neutrons are called these.
Isotopes
When electrons in an atom fall to a lower energy level, they emit this.
Photon (light)
Atomic radius generally does this as you move left to right across a period.
Gets smaller or decreases
In this type of nuclear reaction, two light nuclei combine to form a heavier nucleus, releasing energy.
Fission
This property describes how much mass is packed into a given volume.
density
This subatomic particle has no charge and is found in the nucleus.
Neutrons
Light behaves like what two things?
a wave and a particle
Which is LESS electronegative? Oxygen or Sulfur
Alpha, beta, and gamma are three types of this from unstable atomic nuclei.
Radioactive decay
When a substance changes directly from a solid to a gas without becoming a liquid, the process is called this.
sublimation
According to the quantum mechanical model, this is the region where an electron is most likely to be found.
An orbital or electron cloud
Provide one example of ionizing radiation
X-ray, gammy rays
This element in period 3 has the highest electronegativity.
Chlorine (Cl)
If a radioactive isotope has a half-life of 10 years, what fraction of the original sample remains after 30 years?
1/8th