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Flashcards in Chemistry Unit Test Deck (45):
1

What are the 3 types of Sub-atomic particles and how do you find their number on the periodic table?

Proton- Atomic Number
Neutron- Subtract # of protons from mass number
Electron- Same as protons

2

How many groups of elements does the periodic table have?

18

3

What are valence electrons and how can you use the periodic table to determine the number of them in an atom?

They are the electrons found in the outermost energy level of an atom, on the periodic table, use the group number but drop the teen

4

What are the number of valence electrons for Hydrogen, Calcium, Oxygen,and Neon

Hydrogen-1
Calcium-2
Oxygen-6
Neon-8

5

What are the noble gases and describe their bonding abilities

They are Neon, Argon, Krypton, Xenon, Radon, they do not form bonds with other atoms because they already have a full valence shell

6

Why atoms considered neutral?

The number of electrons equal the number of protons

7

Define and give an example of an ionic bond

bond that forms when electrons are transferred from one atom to another, which results in a positive and negative ion.-NaCl

8

Define and give an example of a metallic bond

bond formed by the attraction between positively charged metal ions and the electrons around them- block of silver

9

Define and give an example of a covalent bond

bond formed when atoms share one or more pairs of electrons- H2O

10

Define Crystal Lattice

the regular patterns in which a crystal is arranged

11

Define ion(s)

CHARGED particles when atoms gain or lose electrons

12

Define atom(s)

NEUTRAL (no charge) because # of protons equal the # of neutrons

13

Define diatomic molecule and give 3+ examples

atom make of 2 of the same molecules- Hydrogen, Oxygen, nitrogen, Fluorine, Chlorine, Bromine, Iodine

14

Define chemical reaction

when one or more substances change to produce one or more different products

15

what are the four signs of a chemical reaction?

Gas formation, solid formation, energy change, color change

16

what happens during a chemical reaction?

bonds break, new bonds form, new substance created

17

define product

substance that forms in a chemical reaction

18

define reactant

substance that participates in a chemical reaction

19

what does the law of conservation of mass state?

Mass cannot be created nor destroyed in a chemical reaction

20

synthesis reaction

2 substances combine to form 1

21

decomposition reaction

compound breaks down to form 2 or more substances

22

single displacement reaction

1 element replaces another

23

double displacement reaction

ions from 2 compounds exchange places

24

define exothermic

energy (heat) RELEASED in a chemical reaction

25

define endothermic

energy (requires heat) is taken in during a chemical reaction

26

define activation energy

minimum amount of energy need to start a chemical reaction- striking a match, spark in a car's engine, light

27

define acid and give properties

liquid with pH level below 7- sour flavor, many corrosive, react with metals, conduct electric current

28

define base and give properties

liquid with a pH level above 7- bitter flavor, many corrosive, slippery feel, conduct electric current

29

define indicator and give examples

substance that changes color in the presence of an acid or base- bromythol blue, pH paper, pH meter, litmus paper strips

30

what 2 substances are always produced in chemical reaction

a salt and water

31

in chemistry, what is a salt?

an ionic compound that forms when a metal replaces the hydrogen of an acid

32

define radioactivity

process by which an unstable nucleus gives off nuclear radiation

33

name the 3 types of radioactive decay

alpha, beta, gamma

34

which RD has the most penetrating power?

gamma

35

name one use of radioactivity in home, industry, and healthcare

home- smoke detectors
industry-space probes
healthcare- tracers

35

Define isotope

atom that has the same number of protons as other atoms of the same element but have a different number of neutrons

36

define half-life

time needed of half a sample of a radioactive substance to undergo radioactive decay

37

fission

splitting of the nucleus of one large atom into 2 or more fragments

38

fusion

combo of nuclei of small atoms to form a larger nucleus

39

what process occurs in nuclear power plants?

fission

40

what process occurs in the sun's core, what state of matter is found, and what temp does it have to be?

Fusion- state of matter- plasma- more than 100,000,000 degrees celsius

41

fusion advantages

less accident prone, less waste, endless supply of fuel in the oceans

42

fusion disadvantages

difficult to create, more energy used to create than is produced

43

fission advantages

cost less that plants that use fossil fuels, no pollution

44

fission disadvantages

more accidents, must be stored until it becomes less radioactive