Chapter 2 Vocabulary Flashcards Preview

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Flashcards in Chapter 2 Vocabulary Deck (39)
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1

Matter

Anything that has mass and takes up space.

2

Element

An element is a substance that cannot be broken down into smaller components by chemical reactions.

3

Trace Element

Elements that are required for the body in minuscule amounts

4

Atom

An atom is the smallest unit of an element.

5

Neutron

An uncharged particle in the nucleus of an atom.

6

Proton

A positively charged particle in the nucleus of an atom.

7

Electron

A negatively charged particle surrounding the nucleus of an atom, it is much smaller that the particles in the nucleus.

8

Atomic Nucleus

The atomic nucleus consists of both protons and neutrons.

9

dalton

The unit DALTON is used to measure atoms as well as other small atomic particles.

10

Atomic Number

The number of protons.

11

Mass Number

The sum of the protons and neutrons of an atom.

12

Atomic Weight

The average of all the isotopes.

13

Isotope

An isotope of an element, is that same element, only with a different number of neutrons.

14

Radioactive Isotope

A radioactive isotope is one in which the nucleus decays spontaneously, giving off particles and energy.

15

Energy

Energy is the capacity to cause change(to do work).

16

Energy Level

The different states of potential energy are called energy levels.

17

Potential Energy

Potential energy is the energy that matter posses because of location/structure.

18

Orbital

The 3-D space in which an electron is found most of the time(90%).

19

Valence Electron

The outer electrons of an atom.

20

Valence Shell

The outermost electron shell of an atom.

21

Chemical Bond

When atoms are close enough to each other, they are attracted and form chemical bonds.

22

Covalent Bond

A covalent bond is the sharing of a pair of valence electrons by two atoms.

23

Molecule

Two or more atoms held together by a covalent bond are a molecule.

24

Structural Formula

The structural formula represents both the atoms, and their bonding as a small diagram or chart(drawings such as: H-H).

25

Molecular Formula

The abbreviated way of writing the structural formula(H^2, instead of H-H)

26

Double Covalent Bond

When an atom shares two pairs of electrons with another atom.

27

Valence

The bonding capacity is called the atom's valence, it is usually equal to the number of unpaired electrons in the outer shell.

28

Electronegativity

The attraction of a particular kind of atom for the electrons of a covalent bond. The more electronegative, the more strongly it pulls the electrons toward itself.

29

Nonpolar Covalent Bond

When a pair of electrons are shared evenly between two atoms.

30

Polar Covalent Bond

When a pair of electrons are shared unevenly between two atoms.