Chapter 17 Definitions Flashcards Preview

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Flashcards in Chapter 17 Definitions Deck (24)
1

What are atoms composed of?

Protons, neutrons, and electrons

2

What happens in 1897?

J.J Thomson discovers the electron (e-). e- has a negative charge.

3

Ernest Rutherford discovered the atom contains a positively charged core called the nucleus.

1911

4

Positive charge(p+) in the nucleus

Proton

5

Particle with no charge in the nucleus(n0)

Neutron

6

Very tiny and orbit the nucleus

Electrons

7

The number of protons found in an atom

Atomic number

8

Atoms of the same element with different numbers of neutrons.

Isotopes

9

What do isotopes do?

Give atoms of a single element different masses. C14, S33

10

Total number of protons and neutrons in the nucleus.

Mass number

11

What are elements named for?

Properties, locations, scientists, planets, Latin or Greek origins

12

Total mass of an atom. Mass of all protons, neutrons, and electrons.

Atomic mass

13

Atomic mass is measured in what?

(Amu) daltons. It takes 6x10 to the 23 Amu to equal one gram

14

What groups can the periodic table be divided into?

Metals and nonmetals

15

Shiny, opaque, malleable, ductile, and good conductors of heat and electricity.

Metals

16

Poor conductors, may be solids, liquids, or gases.

Nonmetals

17

Tells how many occupied energy levels are in each atom of an element. (Rows across)

Period

18

Elements with similar characteristics. (Columns down)

Group (family)

19

Left hand column of periodic table. (Li, Na, K...) most chemically reactive metals.

Alkali metals

20

Very reactive; form ionic bonds. (Ca, Mg, Be...)

Alkaline earth metals

21

The gradual change of any property in the elements across a period (size)

Periodic trend

22

Discovered by Rutherford in 1919. Process of adding a p+ to the nucleus of an atom.

Transmutation of elements

23

What are all the elements right of uranium?

Transmutated, they do not exist in nature.

24

What will transmutated elements do?

They break apart giving off excess protons and neutrons. These particles are radioactive.