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Flashcards in Chapter 2 Deck (21):
1

Matter

Matter refers to anything that takes up space and has mass. Matter can exist as a solid, a liquid, or a gas.

2

Element

One of the basic building blocks of matter; an element cannot be broken down by chemical means. Each element has a name and a symbol. There are only 92 naturally occurring elements.

3

Why are elements arranged in a periodic table?

Elements in a column show periodicity, meaning that each column behaves similarly during chemical reactions.

4

Atom

The smallest unit of an element that still retains the chemical and physical properties of the element. It is the smallest unit to enter into chemical reactions.

5

What subatomic particles help make up an atom?

• Protons - positively charged
• Neutrons - uncharged
• Electrons - negatively charged
Protons and neutrons are located within the nucleus of an atom and electrons move about the nucleus.

6

Proton

Positive subatomic particle, located in the nucleus and having weight or approximately one atomic mass unit

7

Neutron

Neutral subatomic particle, located in the nucleus and having weight of approximately one atomic mass unit

8

Electron

Negative subatomic particle, moving about in an energy level around the nucleus of an atom

9

Electron shell

Average location, or energy level, of an electron in an atom

10

Atomic number

The number of protons within the nucleus of an atom.

11

Mass number

The sum of the number of protons and neutrons in the nucleus of an atom.

12

Atomic Mass

Mass of an atom equal to the number of protons plus the number of neutrons within the nucleus. It is the average of the atomic mass unit (AMU) for all the isotopes of that atom

13

Isotopes

Atoms with the same atomic number but a different atomic mass due to a different number of neutrons present in the nucleus

14

Radioisotope

An unstable form of an atom that spontaneously emits radiation in the form of radioactive particles or radiant energy.

15

Molecule

Union of two or more atoms of the same element; also, the smallest part of a compound that retains the properties of the compound

16

Compound

Substance having two or more different elements united chemically in a fixed ratio

17

What is an Ionic Bond?

Bonding between atoms in which electrons are exchanged to create a stable outer shell (for all atoms?)

Note: atoms with more than one shell are most stable when the outer shell has 8 electrons.

18

Ion

A charged particle that carries a negative or positive charge

19

Covalent Bond

Chemical bond in which atoms share one pair of electrons. The electrons spend part of their time in the outer shell of each atom so that both essentially have a stable outer shell.

20

What 4 main ingredients make up more than 90% human body?

Carbon, nitrogen, oxygen, and hydrogen

21

What are the two types of bonds between atoms?

• Ionic bond
• Covalent bond