This part of the atom contains over 99.9% of its mass.
What is the nucleus?
All isotopes of an element share this feature.
What is the number of protons (atomic number)?
The rings of a Bohr model represent these.
What are energy levels (shells)?
The s sublevel can hold this many electrons.
What is 2?
The definition of a valence electrons is this.
What are electrons in the outermost energy level of an atom?
These particles make up all matter.
What are atoms?
The definition of an isotope is this.
What are atoms of the same element with different numbers of neutrons?
When an electron absorbs energy it does this.
What is moves to a higher energy level?
The noble gas notation [Ne]3s2 identifies this element.
What is magnesium?
Group 1 has this number of valence electrons.
What is 1?
The atomic number identifies this.
What is the number of protons in the nucleus of an atom.
The number of neutrons in Sodium-24 is this.
What is 13?
When an atom's electrons are in the lowest possible energy levels, the atom is said to be in this state.
What is ground state?
This sublevel has 5 orbitals.
What is the d-block (or d sublevel).
Arsenic has this number of valence electrons.
What is 5?
According to modern atomic theory, the number of these subatomic particles can vary among atoms of the same element.
What are neutrons?
The mass number of an isotope is this.
What is the sum of protons and neutrons in the nucleus?
The smallest amount of energy an atom can gain or lose is known as this.
What is a quantum?
What is 4s?
This group of elements has a full shell of valence electrons.
What is the noble gases?
An atom with the same number of protons and electrons is said to be this.
What is electrically neutral?
The atomic mass of an element on the periodic table is usually not a whole number because it is actually this.
What is the weighted average of all naturally occurring isotopes?
When an excited electron returns to the ground state it does this.
What is releases energy as light?
The electron configuration 1s22s22p63s23p64s23d3 this element.
The Lewis dot structure for oxygen has this number of dot pairs.
What is 2?