Chemistry - Unit 2

What makes noble gases unique? (in terms of reactivity and number of valence electrons)

All noble gases have 8 valence electrons in them except helium. As well when the S and P sub-levels are filled, the element is non-reactive.

What is the octet rule?

States that atoms become stable by having 8 electrons in their valence energy level.

What color has the least energy?

Red

What color has the longest wavelength?

Red

What is the difference between atomic number and mass number?

Atomic Number: Number of protons in the nucleus of that element (Non-Whole Number on the Periodic Table) Mass Number: Sum of the protons and neutrons

What is an isotope?

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

Why is atomic mass not a whole number?

Because isotopes have different masses the weighted average is not a whole number.

Identify the element that is represented for each of the following electron configuration. 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p5

Bromine (Br)

What is the difference between an element, a compound, and a mixture?

Element: The simplest form of matter. Cannot be broken down into simpler substances. Compound: Chemical combination of 2 or more elements joined together in a fixed proportion. Mixture: A combination of 2 or more substances. Each element maintains its identity.

Atomic mass is the weighted average of isotopes. In this case, common (abundant) isotopes have a less or greater effect than uncommon ones?

Greater

What happens to an atom when you change the number of protons?

It becomes a different element.

How are the following 2 isotopes of lithium similar? Different? Lithium-6 and Lithium-7.

Lithium-6 has a greater affinity than Lithium-7

Identify the element that is represented for each of the following electron configuration. 1s2 2s2 2p6 3s2

Magnesium (Mg)

The Group 3A elements through the group 8A elements form an area of the periodic table where the electron sub-levels being filled are the p-orbitals, s-orbitals, or d-orbitals?

P-Orbitals

Using the Periodic Table Indicate how many protons, neutrons, and electrons are in the following atoms... Calcium- 40

P: 20 N: 20 E:20

Using the Periodic Table Indicate how many protons, neutrons, and electrons are in the following atoms... Scandium ( Mass Number: 45, Atomic Number: 21 Sc)

P: 21 N:24 E:21

Atomic number dictates how many protons, neutrons, or electrons in the nucleus?

Protons

An element has an electron configuration of 1s2 2s2 2p6 3s2. How many valence electrons does this element have? What is the element have? What does the Lewis Dot Diagram look like?

The element that is Magnesium (Mg) has 2 valence electrons.

An element has an electron configuration of 1s2 2s2 2p6 3s2 3p4. How many valence electrons does this element have? What is the element have? What does the Lewis Dot Diagram look like?

The element that is Sulfur (S) has 6 valence electrons.

What is the relationship between wavelength and energy?

The higher the energy the lower the wavelength and vis versa.

What happens to the average distance of an energy level (shell) from the nucleus as the principle energy level increases?

The more the energy of an electron, the more it will be further from the nucleus. The average distance of an electron energy level increases.

What type of electron transitions produce short wavelengths? Long wavelengths?

The shortest wave length produces the most energy and the longest wavelength produces the most energy.

What color has the greatest energy?

Violet

What color has the shortest wavelength?

Violet

What happens to an atom when you change the number of electrons?

You create Ions.

What happens to an atom when you change the number of neutrons?

You create Isotopes.

What is the electron configuration and the abbreviated electron configuration for the following element: : Arsenic

[Ar] 4s2 3d10 4p3

What is the electron configuration and the abbreviated electron configuration for the following element: : Sodium

[Ne] 3s1

What is the electron configuration and the abbreviated electron configuration for the following element: : Sulfur

[Ne] 3s2 3p4

Use these words to fill in the statements : small, valence, positive, period, protons, neutrons, dense. a) A nucleus is composed of _______________ and _________________. It has a ________________ charge. It is very _______________ and very ___________________. b) If atoms are in the same group they have the same number of ________________ electrons. c) All of the elements in the same ROW are in the same ___________________.

a) Protons, Neutrons, Positive, Small, and Dense b) Valence c) Period