lec1-ai-flashcards

What is the smallest particle an element can be divided into while remaining identifiable?

An atom.

What is the meaning of the Greek word 'atomos'?

Indivisible.

What are the four assumptions of atomic theory?

1) Each element is composed of atoms. 2) Atoms of a given element are identical. 3) Chemical compounds consist of specific ratios of atoms. only whole atoms can combine 4) Chemical reactions change how atoms are combined in compounds.

What charges do protons, electrons, and neutrons have?

Protons have a +1 charge, electrons have a -1 charge, and neutrons are neutral.

Where are protons and neutrons located in an atom?

In the nucleus.

What does the atomic number represent in an atom?

The number of protons in the nucleus.

When atoms have no overall charge …

The number of protons equal the number of electrons

Number of protons or electrons?

Atomic number(z) it is written as a subscript

the total number of protons and neutrons in the nuclues of an atom?

mass number (A)- written as a superscript before the element symbol

How is the mass number of an atom calculated?

By adding the number of protons and neutrons.

What are isotopes?

→Atoms of the same element with different masses.

→They have different number of neutrons but same number of protons.

What is the periodic table?

A systematic organization of elements arranged in order of atomic number.

What is the difference between metals and nonmetals on the periodic table?

Metals are on the left and are shiny and conduct electricity AND solids except (mercury), while nonmetals are on the right and can be solid(carbon), liquid(bromine), or gas(neon).

Metalloids?

On steplike line between metals and non-metals (except Al, Po, and At).

So the metalloids are: B, Si, Ge, As, Sb, and Te

What are the main groups in the periodic table?

1) Alkali metals, 2) Alkaline earth metals, 16) Chalcogens, 17) Halogens, 18) Noble gases.

What is the electron configuration?

The distribution of electrons in an atom.

Electrons occupy certain energy level called ?

Shells

Shell definition?

A grouping of electrons in atom according to energy .

Shell 1 capacity?

2

shell 2 capacity?

8

shell 3 capacity

18

shell 4 capacity?

32

If a shell is farther from the nucleus what will happen?

It will become larger, and will hold more electrons, and the energy of the electrons will increase.

The subshells are?

s,p,d, and f. 

Within the subshells, electrons are group into ___, which is 

Orbitals: region of space within an atom where the specific electron are most likely to be found.

Subshell s has how many orbitals and how many electrons?

1 orbital and 2 electrons

Subshell p has how many orbitals and how many electrons?

3 orbitals and 3(2)→ 6 electrons 

Subshell d has how many orbitals and how many electrons?

5 orbitals, and 5(2)=10 electrons

Subshell f has how many orbitals and how many electrons?

7 orbitals, and 7(2)=14 electrons

What is the ground state of an atom?

The lowest possible energy configuration of electrons. Its the most stable organization.

What are the three rules for writing electron configurations?

1) Electrons occupy the lowest energy orbitals available. 2) Each orbital can hold only two electrons of opposite spin. 3) Orbitals of the same energy are half-filled before any are completely filled.

How are condensed electron configurations written?

Put the noble gas before it in brackets and then the valence electrons.

What are valence electrons?

Electrons in the outermost shell of an atom.

What is the maximum number of electrons that can fit in the first four shells?

1st shell: 2, 2nd shell: 8, 3rd shell: 18, 4th shell: 32.

What is the difference between core electrons and valence electrons?

Core electrons are the filled inner shell electrons, while valence electrons are those in the outermost shell.

What are orbitals and how many orbitals are in each subshell type?

Regions where electrons are likely found; s has 1 orbital, p has 3, d has 5, and f has 7.

What does the superscript denote in an electron configuration?

The number of electrons in the corresponding orbital.