lecture-chapter4

Question 1

what is chemistry?

Answer 1

the study of makeup structure, properties of substances and the changes that occur to them. the study of matter.

Question 2

what is atom?

Answer 2

smallest unit of any elemental substance that maintains the characteristics of that substance.

Question 3

what make up an atom?

Answer 3

subatomic particles.

Question 4

what does nucleus contain(central core of an atom)?

Answer 4

+change protons and neutrons-no charge.

Question 5

where is -charged electrons?

Answer 5

spin around the nucleus in an orbital.

Question 6

what is an element?

Answer 6

substance that contains only one kind of atom.

Question 7

what determine the element of an atom?

Answer 7

the number of protons.

Question 8

what are elements organized by?

Answer 8

structure and chemical properties in the periodic table.

Question 9

what is a system of symbols used to?

Answer 9

identify elements.

Question 10

what does Chart show?

Answer 10

how elements relate and react to one another.

Question 11

what does each cell give?

Answer 11

the symbol of the chemical element and includes the atomic number and atomic mass.

Question 12

what is atomic number?

Answer 12

number of protons in the nucleus in each atom of that element.

Question 13

what is atomic mass?

Answer 13

sum of the masses of the protons and neutrons in an atom.

Question 14

what does organization of the cell indicates?

Answer 14

how elements interact chemically.

Question 15

how are elements are grouped?

Answer 15

metal(left)or nonmetals(right)

Question 16

what are compounds?

Answer 16

substance in which 2 or more elements chemically combine

Question 17

what is the basic unit of any compound?

Answer 17

molecule

Question 18

what is table salt?

Answer 18

Na-Cl

Question 19

what is chemical formula?

Answer 19

combination of symbols of elements making up a compound that represents one molecule or unit of a compound. Has the symbol and subscript numbers of atoms for each element in the compound.

Question 20

what does- know how to read a chemical formula help?

Answer 20

identify the elements in the substance.

e.g. H20–>2 hydrogen and 1 oxygen atom.

Question 21

what can chemistry formulas indicate?

Answer 21

how atoms are arranged in a molecule.

Question 22

what does structural formula for carbon based compounds show?

Answer 22

how atoms connect to the carbons.

Question 23

what is acetic acid chemical formula?

Answer 23

C2H4O2

Question 24

what is acetic acid structural formula?

Answer 24

CH3COOH

Question 25

what is chemical bond?

Answer 25

force that holds 2 atoms together.

Question 26

what form bond?

Answer 26

electrons

Question 27

how many e- does each orbital contain?

Answer 27

2

Question 28

what is shell?

Answer 28

the space around the nucleus with one or more orbitals.

Question 29

how many shells does atoms have(max)?

Answer 29

7

Question 30

when are atoms most stable?

Answer 30

when outer shell is full of e-

Question 31

when are atoms not stable?

Answer 31

share or transfer e- from another atom.

Question 32

what does each colun,group in the periodic table have?

Answer 32

same number of e- in the outermost shell.

Question 33

when does an ionic bond occur?

Answer 33

e- are transferred from one atom to another.

Question 34

what does ionic bond creates?

Answer 34

a -charge in one atom and a +charged charge in the other.

Question 35

what is ion?

Answer 35

an atom with a + or - electrical charge

Question 36

what is cation

Answer 36

+ charge ion

Question 37

what is anion

Answer 37

- charge ion

Question 38

what happen to identical charge?

Answer 38

repel each other

Question 39

what happen to opposite charge?

Answer 39

attract each other

Question 40

what are the 3 characteristics for the substances with ionic bonds?

Answer 40

- have a crystalline晶体的structure - dissolve in water - metals and nonmetals

Question 41

when does covalent bond form?

Answer 41

atoms share one or more pairs of e-

Question 42

how to form water?

Answer 42

oxygen share 2 e- in its outer shell with 2 hydrogen atoms.

Question 43

how many shells (max) can surround the nucleus? how many e- can first shell hold? how many e- can the rest shell hold?

Answer 43

7 2 8

Question 44

what is lewis structure?

Answer 44

shorthand option of diagramming a valence electron

Question 45

how many e- can a shell hold max?

Answer 45

8

Question 46

how a e- be represented? and what is valence e- ?

Answer 46

by dot next to the symbol. | e- in partially full shells that are likely to be shared or transferred.

Question 47

when does a double bond form?

Answer 47

when 2 atoms share 2 pairs of electrons.

Question 48

what does the number of valence e- around the atoms equals to?

Answer 48

the number of balance e- in the molecule.

Question 49

what is the pure substance?

Answer 49

the matter in which all the basic units are the same. -grouped as elements or compounds.

Question 50

how does the compounds categorized?

Answer 50

organic compounds or inorganic compounds.

Question 51

what does organic compounds contain?

Answer 51

chains or rings of carbon

Question 52

what does inorganic compounds contain?

Answer 52

no carbon or only single carbon atoms.

Question 53

what are mixtures?

Answer 53

substances that are put together but not chemically combined.

Question 54

what does homogeneous mixtures have?

Answer 54

a uniform统一的 distribution of particles.

Question 55

what does heterogeneous mixtures have?

Answer 55

a nonuniform distribution of particles.

Question 56

what are most homogenous mixtures?

Answer 56

solution in which a solute is dissolved by a solvent.

Question 57

what does a physical change involve?

Answer 57

changing shape, size, temp and physical state.

Question 58

what is phase change?

Answer 58

a physical change in visible structure without changing the molecular structure.

Question 59

Any phase change is an example of _?

Answer 59

reversible physical change.

Question 60

when is a chemical change occur?

Answer 60

whenever new substances with different chemical and physical properties are formed.

Question 61

what will change if a different chemical and physical properties are formed?

Answer 61

produce a change in color, odor, or flavor or releases a gas.

Question 62

what will physical and chemical changes be?

Answer 62

may or may mot be reversible.

Question 63

what are fluids?

Answer 63

substances that have characteristics of liquids and gases.

Question 64

what type of fluids have characteristics of liquids and solids?

Answer 64

non-newtonian fluids.

Question 65

what are chemical formulas used to?

Answer 65

represent the compounds involved in a chemical change.

Question 66

what are reactants?

Answer 66

chemical formula on the left side.

Question 67

what are products?

Answer 67

chemical formula on the right side.

Question 68

what does the law of conservation of matter state?

Answer 68

matter can be changed, but not created or destroyed. --shown in chemical equations.

Question 69

how can equations must balance by?

Answer 69

having the same number of each type of atom on both sides of the equation.

Question 70

what are atoms composed of?

Answer 70

– a nucleus containing protons and neutrons – electrons moving about outside the nucleus

Question 71

what is periodic table?

Answer 71

a chart that shows how elements relate and react to one another

Question 72

what do atoms create? how?

Answer 72

form ionic and covalent bonds to create molecules and compounds.

Question 73

what does pure substances have? what is pure substances?

Answer 73

same basic units. | mixtures are substances put together, but not chemically combined

Question 74

how can changes to food compounds be described?

Answer 74

both physical and chemical

Question 75

what are chemical equations used to?

Answer 75

describe chemical changes