Unit 1 - the atom

What are the three basic subatomic particles?

protons, neutrons, and electrons

What is contained within the nucleus of the atom?

The nucleus of an atom is described as a small, dense center surrounded by electrons orbiting at various levels. The nucleus of the atom contains protons and neutrons, which are responsible for almost all of the mass of an atom. Together, protons and neutrons are referred to as nucleons.

Which part of the atom is positively charged?

Protons

Which part of the atom is negatively charged?

Electrons

Which part of the atom is neutral?

Neutrons

Which subatomic particle is the smallest?

Electrons, which are located outside of the nucleus, are the smallest subatomic particle due to a mass of only 1/1,826 that of a proton

Which subatomic particles are equal in number within a neutral or stable atom?

In a neutral atom, the number of protons is equal to the number of electrons. This balance of positive and negative charges makes the atom's overall charge zero.

List the subatomic particles in order of largest to smallest.

Neutrons → protons → electrons

What part of the atomic mass is the heaviest?

Proton + neutrons

Are atoms neutral?

Typically unless an ion is present

If an atom has electrons and protons that are equal numbers, what is the net charge?

0

What are nucleons?

Neutrons + protons

What is an ion?

Add or remove electrons; then changes the charge positively and negatively

What is the Z number?

Atomic number

What is the A number?

Atomic mass number

What is the atomic number, or Z #?

Number of protons, distinguishes elements

What is the atomic mass number, or A#?

Number of protons and neutrons (nucleons) combined

What is it called when an element has the same number of protons, but different number of neutrons?

Isotopes

If lead has a Z number of 82, how many protons and how many electrons are present?

82 protons, 82 electrons

How do you find the neutrons within an atom?

Atomic mass number(a) - atomic number(z) = neutrons

What is the distinguishing characteristic of an element?

its number of protons; each element has a unique number of protons in its nucleus, known as its atomic number

What formula is used to calculate the maximum number of electrons in each orbital shell?

2n²

How many electrons can exist in the outermost shell?

A maximum of 8 electrons can exist in the outermost shell of an atom. When the outermost shell contains 8 electrons, the atom generally has a stable electron configuration, known as the octet rule.

What is the maximum number of electrons that can exist in the N shell?

(n = 4), so 2(4²) = 2(16) = 32 electrons

List and explain the two things that affect the binding energy of an electron.

distance from the nucleus and the number of protons in the nucleus (atomic number)

What is the difference between a neutral atom and an ion?

A neutral atom has an equal number of protons and electrons, giving it an overall charge of zero. An ion is an atom that has gained or lost electrons, causing it to have an electrical charge. If an atom loses electrons, it becomes a positive ion, and if it gains electrons, it becomes a negative ion.