Elements and Symbols
Which elements correspond to H, Be, B, F, and Ne?
Hydrogen, Beryllium, Boron, Flourine, and Neon
Name for number above chemical symbol?
atomic number
Radioactive decay
spontaneous breakdown of atom's nucleus which often changes the element of the atom
Light has a wavelength of 34.4 nm. What is its wavelength (in m) and its frequency?
3.44 x 10-8, 8.72 x 1015 Hz
What is biggest difficulty in making nuclear bomb?
isotopic enrichment
Which elements correspond to Na, Mg, P, Ar, and K?
Sodium, Magnesium, Phosphorous, Argon, and Potassium
What does atomic number tell you?
number of protons (and electrons in element)
Physical Constant
quantity in nature that never changes
A specific isotope of silicon has a mass of 4.814 x 10-23
What is it's mass in amu? (1 amu = 1.66 x10^-24 g) Is it the most abundant isotope of Silicon?
29.0 amu, not most abundant
How many protons, neutrons, and electrons are in Ar-40 or argon-40?
18 protons and electrons, 22 neutrons
What are the chemical symbols for Helium, Lithium, Carbon, Nitrogen, and Oxygen?
He, Li, C, N, O, F
Name for number below chemical symbol?
atomic mass
Ground state
lowest energy state of a particle
Yellow light has frequency of 5.1 x 10^14 Hz. What is its wavelength and energy in one photon?
5.9 x 10^-7 m, 3.4 x 10^-19 J
An atom has 35 protons, 45 neutrons, and 35 electrons. What is its symbol (including the mass number)?
Br-80
What are the chemical symbols for Scandium, Silicon, Sulfur, Chlorine, and Calcium?
Sc, Si, S, Cl, Ca
What does atomic mass tell you, and what is it's units?
average mass of atom of an element, amu (atomic mass units)
spectroscopy?
identifying chemicals by the light they emit or absorb
A photon has a wavelength of 94 nm. What frequency does it have?
3.2 x 10^15 Hz
The electron of a hydrogen atom is in the n=1 orbit. It absorbs light with a wavelength of 103 nm and jumps to the n=3 orbit. If the electron of another hydrogen atom is in the n=3 orgit, what wavelength of light must it emit to get to its ground state?
103 nm
Why are some symbols like K for Potassium not the 1st letter(s) of the name?
Come from Latin
Atomic mass = number of ______ + number of _________
neutrons, protons
electromagnetic waves
all light - visible and invisible
What is the mass of an average potassium atom in grams?
6.49 x 10^(-23) g
The electron of one hydrogen atom moves from the n=4 orbit directly to its ground state. The electron in another hydrogen atom moves from the n=6 orbit directly to its ground state. Which electrons released a photon with the longer wavelength? Which released a photon with the higher frequency?
longer wavelength, from n=4
higher frequency, from n=6