Chem

Proton

Positive

Neutron

Nuetral

Electron

Negative 

Charge of nucleus= 

Atomic number 

What is the atomic number?

Number of 

Number of protons=

Charge of Nuclues

Atomic number=

Number of protons

Where are electrons located?

Orbitals outside the nucleus

What does energy levels show?

Energy levels show how far the electron is from the nucleus

What energy level is closest to the nucleus

Shell #1

Electrons in the first energy level have the lowest energy 

True

What energy level does the second shell have 

More than the first shell 

The 3rd shell has more energy then both shell 1 and 2

True

Conclusion 

The closer the shell is to the nucleus the lower energy levels 

Where are electrons found?

Electrons are found in orbitals

What is an orbital

Region where a electrons most likely found 

The number of electrons found in a neutral atom=

Atomic number (number of protons)

If you know the number of protons then you know the number of electrons in a neutral atom

True

Conclusion

Number of protons= number of electrons *only in a nuetral atom

Ground state

Electrons fill orbitals without leaving any empty space

What is the unstable condition called 

Excited state 

The excited state is temporary 

True 

Ground state 

Lowest possible state filling up atoms in order (2-8-18-32)

Excited state

Atom with excess energy- electrons have absorbed energy or gotten more energy

All atoms of a given element have the

Same number of protons

Elements are different because they contain

Different numbers of protons 

Atomic number=

number of protons in the nucleus of an atom of that element

Atomic number

identifies an element

all atoms are electrically nuetral

True

Therefore the number of electrons (negative charged) must equal the number of protons (positively charged) 

True

Number or neutrons+ mass of protons 

Mass number 

The total number of protons and neutrons in an atom is the mass number 

True 

If you know the atomic number and the mass number of an element 

You can determine the atom’s composition 

The number of neutrons in an atom is the difference between the mass number and atomic number 

True

Mass number can vary in different atoms of the same element

True

Isotopes

Atoms with the same number of protons but different number of neutrons

Neutrons can vary

Therefore mass number can vary as well

The atomic number and mass number are needed to

Determine an atoms composition

The atomic number gives the number of protons which equals the number of electrons

True

The number of neutrons is the difference (subtract) between the mass number and the

Atomic number