Chem Test #1

Question 1

Physical vs. chemical change

Answer 1

Physical: A change in state, shape, and form. No new substances are produced. (Ice melting)

Chemical: Results in the formation of a new substance or substances.

Question 2

Physical vs. Chemical Properties

Answer 2

Physical: color, density, hardness, and melting and boiling points
Chemical: ability of a substance to undergo a specific chemical change

Question 3

Atom, ion, isotope, ionic isotope

Answer 3

Atom: nothing
Ion: charged
Isotope: diff neutron number
Ionic isotope: charged isotopes

Question 4

How do we find protons, neutrons, and electrons?

Answer 4

Protons: atomic #
Neutrons: atomic # - mass #
Electrons: atomic # if neutral

Question 5

Ionic vs molecular compounds

Answer 5

Ionic: Metals & nonmetals
Molecular: nonmetals & nonmetals

Question 6

Cations vs. Anions

Answer 6

Cations: positively-charged ions (have more protons than electrons due to having lost one or more electrons).

Anions: negatively-charged ions (have more electrons than protons due to having gained one or more electrons).

Question 7

Metals vs. Non-metals

Answer 7

M: Element that is malleable and ductile and is a good conductor of heat and electricity

NM: Elements that are grouped together mainly because they do not resemble metals. Are poor conductors of heat

Question 8

Name the groups (alkali metals, halogens, etc.) - what are their trends?

Answer 8

Alkali metals: group 1, most reactive

Alkaline earth metals: group 2

Halogens: most reactive nonmetals

Noble gases: least reactive

Question 9

Classification of Matter

Answer 9

Mechanical/Heterogeneous: different parts are visible (pizza)

Solution/Homogeneous: looks the same throughout

Element: 1 atom, cannot be broken down

Compound: 2+ atoms, can be broken down

Question 10

Types of equations

Answer 10

Word: chemical equation writing in words (magnesium + oxygen gas -> magnesium oxide)

Skeletal: chemical formulas of all the reactants and products (Mg + 02 ->
MgO)

Balanced: ensures the law of conservation of mass is true. Big # infront is added so the same # of each type of element is on both sides of the equation (2Mg + 0^2 -> 2MgO)

Question 11

Components of a chemical equation

Answer 11

Reactants —> Products

Question 12

Location of subatomic particles

Answer 12

Protons & Neutrons: inside nucleus
Electrons: outside nucleus (shells)

Question 13

7 Diatomic Gases

Answer 13

H, O, F, I, N, Br, Cl

Question 14

Law of Conservation of Mass

Answer 14

States that in a chemical reaction, the total mass of the reactants is always equal to the total mass of the products.
(Mass of reactants = mass of products)

Simply put, in a chemical reaction, the number of each type of atom does not change.

Question 15

Molecular vs. Ionic compounds (bonding)

Answer 15

lonic: DONATES an electron to the other atom in the bond

Molecular: electrons are SHARED equally between the atoms

Question 16

Molecular vs. Ionic compounds (properties)

Answer 16

Molecular:
-low melting & boiling points
-low solubility
-poor conductors of electricity

lonic:
-all form crystals
-hard & brittle
-good insulators
-high melting & boiling points
-good conductors of electricity when dissolved in water