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Flashcards in C16 Terms Deck (45):
1

law of definite proportions

Established that masses if chemical substances combine in definite repeatable ratios

2

core-envelope model

Based on the caloric theory

3

plum-pudding model

Atoms are masses that have a positively charged (pudding) in which the negatively charged electrons stay

4

nuclear model

Every atom has a nucleus and electrons circle around it

5

planetary model

Electrons circle around the nucleus

6

quantum model

Electrons move in waves around the nucleus

7

orbital

Subregions of space

8

nucleon

Neutrons and protons in the nucleus

9

elementary particle

Subatomic particles that are the building blocks of photons neutrons and electrons

10

atomic number (Z)

The number of protons in the nucleus

11

isotope

Aims of elements that have different numbers of neutrons

12

mass number

Tells isotopes apart

13

isotopic notation

Shows both the atomic and mass numbers of the element

14

atomic mass

The mass of an electron expressed in atomic mass units

15

atomic mass unit (u)

The mass equal to 1/12th the mad of a carbon atom

16

energy level

Represent the regions where an electron with a certain amount of energy is most likely to be found.

17

electron configuration

Is the arrangement of the energy levels and the positions that electrons can take within those energy levels for a given number of electrons.

18

valence electron

The electrons in the outermost energy level

19

nuclear chemistry

The study of changes in atomic nuclei

20

radioactivity

The emission of nuclear radiation

21

nuclear radiation

The rays and particles emitted by unstable nuclei

22

alpha particle

Positively charged particles

23

beta particle

Negatively charged particles

24

gamma decay

A nucleus shedding energy by releasing gamma rays

25

alpha decay

The atoms nucleus loses two protons and two neutrons

26

beta decay

The atom loses a beta particle and emits gamma rays

27

radioactive dating technique

Using nuclear decay to date things

28

nuclear bombardment reaction

When a nucleus is stuck by a high energy particle

29

nuclear fission

The splitting of an atom

30

chain reaction

When one atom after another is broken apart

31

nuclear fusion

The crushing of two atoms to form a larger atom

32

What is the most important aspect of a scientific model?

It has to work

33

Discuss one aspect of John Dalton's atomic model that was set aside by a later discovery.

The core envelope model was based on the caloric theory

34

What was the most significant question about the atom after Thomson's discovery of the electron?

The extra mass that was measured

35

What phenomenon did Niels Bohr observe that convinced him that every atom has a unique electron structure?

How light was refracted

36

How do orbitals in the quantum model of the atom differ from orbits in the planetary model?

There exact position can't be found

37

What is the most important use of an elements atomic number? What else an we know from a neutral atoms atomic number?

To tell elements apart. The number of electrons

38

How do atoms of the same element differ?

In the number of electrons

39

Explain the difference between an atoms mass number and atomic mass. Why are both needed in chemistry?

Mass number is the mass of the whole atom and atomic mass is the added mass of all the particles in the atom. Mass number and atomic mass can differ.

40

What arrangement of electrons is usually the most stable for an atom?

When there is 8 electrons in the outermost sphere.

41

(True or false) The element oxygen has eight valence electrons.

True

42

What makes an element radioactive? Which elements found in nature have mainly radioactive isotopes?

When the nuclei is unstable. Polonium though uranium.

43

What kinds of changes to a nucleus occur for each kind of nuclear decay?

For gamma decay there is no change except the nuclei loses energy. For alpha decay two protons and two neutrons are lost. For beta decay a beta particle is lost.

44

What is the source of energy released in fission and fusion reactions?

The nucleus.

45

What are the two most difficult aspects of producing fusion energy for electrical generation?

Making a container to hold the particles in and heating the particles to the right temperature.