A2 Elements combine to form substances

chemistry flashcards grade 10

metals

shiny, malleable, ductile elements

metalloids

elements w/properties intermediate between non-metals and metals

non-metals

do not produce heat/electricity, are structurally brittle

malleable

description of a substance that can be beaten or rolled into sheets w/o crumbling

ductile

description of a substance that can be drawn or stretched into long wires (stretchy)

inert

unreactive with all but the most corrosive of acids

molecule

group of non-metallic atoms bound together by covalent bonds; can be made up of atoms of the same element or atoms of different elements

periods

1-7 horizontal row (aotmic # and mass both increase as you move across)

group/family

1-18 vertical (similar chem. properties as you move down elements get larger in size and less reactive)

alkali metals

soft, shiny, silvery reactive w/water, GROUP 1

alkaline-earth metals

shiny silvery not as soft as alkali's GROUP 2

noble gasses

extremely unreactive non-metals GROUP 18

halogens

non metals, poisonous, react readily with alkali metals to form salts; fluorine, iodine, bromine, chlorine GROUP 17

subatomic particles

protons neutrons and electrons

isotopes

atoms of the same element containing diff numbers of neutrons

atomic molar mass

avg. molar mass of an elements atoms, including those of all the elements diff isotopes

ionization

the process of gaining/losing electrons

ion

an electrically charged atom/group of atoms

cation

positively charged atom (usually formed when metal atoms lose electrons)

octet rule

atoms bond in such a way as to have 8 electrons in their valence energy level

valence electrons

the electrons in the outer level; electrons participate in bonding

elements in the same family have...

the same # of valence electrons = similar chemical properties

formation of ions

gain or loss of electrons through the process of ionization, the # of protons + neutrons stays the same

formation of isotopes

the number of protons and electrons stays the same, named by changing the eneding of the element to -IDE

crystal lattice

organized array of ions

formula unit

smallest amt. of an ionic compound w/the composition shown by the chemical formulas number of + and - ions in the smallest whole number ratio that results in a neutral unit in the crystal lattice of a compound

ionic bonding

type of bond formed when electrons transfer between metals and non-metals

NaOH(s) - common ionic compound

lye, sodium hydroxide, unclog drains

NaHCO3(s) - common ionic compound

baking soda, sodium hydrocarbonate, raises bread and cakes by giving off CO2 when heated

Mg(OH)2(s) - common ionic compound

milk of magnesia, magnesium hydroxide, works as antacid and laxative

NaCl(s) - common ionic compound

table salt, sodium chloride, adds salty taste in foods

KHC4H4O6(s) - common ionic compound

cream of tartar, potassium hydrogentartrate, mixes w/baking soda to make baked goods rise

ionic compounds

consist of a metal and a non metal

ionic bond

ionic compounds are formed by atoms STEALING electrons to obtain a full valence orbital

naming ionic compounds

name the cation 1st by using the elements name (usually a metal ion), name the anion 2nd by using the 1sst part of the elements name and changing the last part to "ide" (usually a non-metal)

multivalent elements

elements w/more than one stable ion (iron, lead)

polyatomic ions

charged particle made up of several non-metallic atoms joined together

covalent bonds

bond formed when non-metallic atoms share electrons

molecular element

element that forms molecules made up only of its own atoms

diatomic

molecule composed of two atoms of the same element

C12H22O11(s) - common molecular compound

sugar, sucrose, sweetener

C2H6O(l) - common molecular compound

ethanol, component of alcoholic beverages

CH3COCH3(l)- common molecular compound

acetane, solvent

CH4(g) - common molecular compound

methane, heating fuel

monatomic

C(s), noble gasses (helium, neon, argon, krypton, xenon, radon), all metals

diatomic

O3(g) aka ozone, the gens - hydrogen, nitrogen, oxygen, halogens (fluorine, chlorine, bromine, iodine)

prefix numbers

mono, di, tri, tetra, penta, hexa, hepta, octa, ennea, deca

water

H2O(l)

hydrogen peroxide

H2O2(l)

ammonia

NH3(g)

sucrose

C12H22O11(s)

methane

CH4(g)

propane

C3H8(g)

methanol

CH3OH(l)

ethanol

C2H5OH(l)

hydrogen sulfide

H2S(g)

identifyng ionic compounds

if formula starts w/a metal or NH4, its ionic

properties of ionic compounds

high melting point, retention of crystal shape, solubility in water, conductivity in solution

polar

ibject that has a + electric charge at one end and a - charge at the other end

electrolytes

solution that conducts electricity; ionic compounds

properties of molecular compounds

s/g/l @ room temp, low melting/boiling point (covalent bonds are weak), cruble easily when broken, only some are soluble in water, tend to be insulators

properties of acids

sour, not slippery, reacts w/metals (H gas is produced) some metals are better at resisting attack by acids, conductive

properties of bases

bitter, slippery, no reactions w/metal, conductive

buffer

substance that keeps the pH of a solution nearly constant despite the addition of a small ammount of acid/base

when acids/bases are...

neutralized, they lose their characteristic properties

HCl(aq)

hydrochlric acid or aqueous hydrogen chloride, muriatic acid, concrete cleaning

H2SO4(aq)

sulfuric acid or aqueous hydrogen sulfate, battery acid, car batteries, fertilizer manufacturing

HNO3(aq)

nitric acid or aqueous hydrogen nitrate, fertilizer manufacturing, metal refining

H3PO4(aq)

phosphoric acid or aqueous hydrogen phosphate, sour taste in soft drinks, fertilizer manufacturing

HCOOH(aq)

methanoic acid, formic acid, wool dyeing, leather tanning

CH3COOH(aq)

ethanoic acid, acetic acid, vinegar

acids can be identified by...

the presence of H or -COOH

naming acids

name as if ionic compound. hydrogen_ide -> hydro_ic acid, hydrogen_ate -> _ic acid, hydrogen_ite -> _ous acid

naming bases

like naming ionic compounds - metal first

bases can be identified by...

the presence of OH or NH4, usually solid ionic compounds

NaOH(s)

sodium hydroxide, caustic soda, drain cleaner

KOH(s)

potassium hydroxide, caustic potash, leather tanning

NH4OH(aq)

ammonium hydroxide, ammonia solution, window cleaner

Ca(OH)2(s)

calcium hydroxide, milk of magnesia, laxative, antacid

Mg(OH)2(s)

magnesium hydroxide, milk of magnesia, laxative, antacid

Al(OH)3(s)

aluminum hydroxide, antacid, waste water treatment

neutralization

process in which acids and bases react w/eachother so that the H+ion and the OH- ion combine to make a single water molecule, the reaction creates water + a neutral salt