Chem and peanut brittle
nitrogen
78% of the air you breath is made up of what element
physical
P/C adding sugar to coffee
chemical
P/C burning a piece of paper
physical
P/C cutting cake
physical
P/C mashing potatoes
physical
P/C melting ice
chemical
P/C souring milk
false
T/F a chemical reaction either creates or destroys matter
false (amount of atoms)
T/F a mole measures atomic mass
false
T/F a nucleus is an uncharged subatomic particle
true
T/F a pure substance is made of only one kind of material and has definite properties
true
T/F an atom may become more stable by gaining electrons
true
T/F atomic mass reflects the different quantity of neutrons that occur naturally in atoms
true
T/F atoms consist of protons neutrons and electrons
true
T/F atoms in an ionic compound lose their orginal properties and gain new ones
false
T/F atoms of the same element all have the same mass number
false
T/F chemical reactions are never reveresible
true
T/F chemical reactions that are begun by the behavior of electrons
false
T/F electrons that are nearest to the center of an atom have the most energy
trie
T/F elements and compounds are examples of pure substances
true
T/F ionic bonding is another name for electron transfer
true
T/F oil and vinegar salad dressing is an example of a mixture
false
T/F the number of atoms present after a chemical reaction exceeds the combined number of atoms in the original substances
false
T/F the properties of a compound are the same as the properties of the element in that form
false
T/F you can tell what element an atom makes up by the number of neutrons it contains
chemical
________________ properties cannot be seen
electrons
________________ travel in paths around an atoms nucleus
covalent
_________________ bonding creates a neutral molecular compound
products
__________________ are the result of a chemical reaction
ionic
__________________ compounds consist of positively and negatively charged atoms
ionic bond
a bond formed by transfer of electrons between atoms
physical
a characteristic that can be observed or measured without changing the substance into something else is know as a _________________ property of matter
compound
a formula describes a __________________
stability
a need for __________________ is what causes atoms to bond chemically
neutron
a negatively charged particle found in the nucleus
electron
a negatively charged particle that moves around the nucleus of atom
chemical
a reaction between hydrogen and nitrogen that produces a compound would be written as a _______________ equation
irreversible
a roast that is cooked and sliced for a meal has undergone chemical and physical processes that are _____________________
gas
a substance is easily compressed in its _____________ phase
compound
a substance made of two or more different elements chemically joined together
element
a symbol represents and ________________
solid
adding compression would have the least affect on a _______________
molecule
an atom is to an element as a ____________ is to a compound
eight
an atom with ________________ electrons in its outermost level is least likely to react with others
eight
an atom with ________________ electrons in its outermost level is most likely to be stable
atomic
an elements _______________ number equals the quantity of protons in one of its atoms
matter
any thing that takes up space and has mass
matter
anything that has mass and occupies a given space is considered ___________________
mass
atomic mass is an averaged ________________ number
ionically
atoms bond ________________ in order to achieve chemical stability
ion
by accepting or giving up electrons an atom becomes a _______________
mole
by knowing one ________________ of an element scientists can create useful compounds
carbon
carbohydrates are made from what element
covalent bond
chemical bond formed when atoms share electrons with each other
covalent compounds
compounds formed by charing electrons in atoms
ionic compounds
compounds that result when metals and nonmetals bond ionically with each other (ex. salt)
physical
different types of matter can be distinguished by their _______________ properties
physical
dissolving a solution is a ________________ change
ionic
electron transfer between metals and nonmetals creates ________________ compounds
shared
elements in a periodic table are arranged according to _________________ properties
reversible
elements in fertilizer break down in the soil and are recombined as nutrients in the plants roots. This demonstrates __________________ chemical change
chemically
elements join _______________ to create compounds
crystalline
fudge nougat and fondant are types of this type candy
carbon
graphite, diamond, limestone, and charcoal are all a type of what element
diatomic
hydrogen is a _______________ element; colorless odorless and tasteless
16
if helium's atomic mass is 4.0 then the mass of four moles of helium is ______________ g
physical
if the sugar in a bowl of cereal dissolves in the milk it undergoes a ________________ change
pure
if you know the properties of a _________________ substance, you can identify it from all the others
non crystalline
lollipops candy canes and caramel are this type of candy
substances mixtures
major classes of matter include pure ______________ and _______________
phase
melting and boiling points are most related to a substances ______________
fixing
nitrogen gets into the food supply thrugh a process called nitrogen ________________
several
one difference between an element and a compound is that a compound includes _______________ elements
molar mass
one mole of an element is equal to the atomic mass in grams
carbon
organic compounds contain the element ____________
solid
phase of matter that can be seen; takes up definite amount of space with definite shape and slow moving particles
liquid
phase of matter that can be seen; takes up space and shape of container
gas
phase of matter that cannot be seen; does not have shape or volume
ionic
salt is a(n) _____________ compound
property
sourness is a __________________ of lemons
solution
steam rising from a bowl of hot soup is considered a ________________
proton
subatomic particles with positive electrical charge; determines the number of an element
random
substances are distributed in ________________ proportion throughout a heterogeneous mixture
Al
symbol for aluminum
N
symbol for nitrogen
Na
symbol for sodium
S
symbol for sulfur
chemical
the ability of a substance to react with other substances and therefore changing substance, describes ________________ property of matter
molecule
the basic unit of certain compounds is the _______________
chemical
the breakdown of salt into the elements that compose it is a ____________ change
atomic mass
the mass of a chemical element expressed in atomic mass units
sugar
the name of the compound C6H12O6
caffeine
the name of the compound C8H10N4O12
salt
the name of the compound NaCl
sodium bicarbonate
the name of the compound NaHCO3
atomic number
the number of protons in the nucleus of an atom, which determines the chemical properties of an element and place in the periodic table
can
the process that forms compounds can/can't be reversed
elements
the simplest form of matter that can exist under normal laboratory conditions
atom
the smallest unit of matter
solution
the substances in a __________________ may not be apparent
C
the symbol for carbon
H
the symbol for hydrogen
O
the symbol for oxygen
P
the symbol for phosphorous
mass number
the total of protons and neutrons in the nucleus
non crystalline
this candy comes from a very saturated solution (no crystals)
crystalline
this candy contains many small fine crystals of sucrose
crystalline
this candy has a lower sugar concentration
non crystalline
this candy has a sucrose solution boiled at a higher temp
crystalline
this candy has a sucrose solution boiled at a lower temp
non crystalline
this candy has higher sugar concentration
heterogeneous
this mixture is not pure; made of different visible substances (chunky soup)
homogeneous
this mixture is pure; made of different substances not identified by sight (milk, tomato soup, etc)
non crystalline
this type of candy is hard and brittle
crystalline
this type of candy is smooth and creamy
gas liquid solid
three phases of matter
atomic mass
to find the molar mass of an element you need to know its _____________________
mole
unit of measurement used to count atoms or molecules
atoms
using moles is convenient because it's a practical way to measure quantities of _______________
molecule
water and carbon dioxide are examples of these. They are the smallest unit of a molecular compound
physical
water undergoes a _______________ reaction when it boils
atom
what are the smallest particles of an element that can keep its chemical properties? These are building blocks of matter
sulfur
what element has compounds that are used to preserve foods
hydrogen
what element is the lightest known gas
18
what percent of a person's body weight is made up of carbon
protein
when a food is high in nitrogen that means it is high with ________________
moles
you would report the large number of atoms in a sample of sulfur as _______________