science final
T/F there are about 50 known elements on Earth
F
T/F water is often called the universal solute
F
what is the octet rule?
8 valence electrons
what is a horizontal row of elements in the periodic table called?
group
what is each vertical column on the periodic table called?
group
what is a mixture that is not the same throughout called?
heterogeneous
air element, compound, homogeneous or heterogeneous mixture
heterogeneous mixture
mint chocolate chip ice cream element, compound, homogeneous or heterogeneous mixture
heterogeneous mixture
what is a suspension?
heterogeneous mixture
what is seawater an example of? because it is the same throughout
homogeneous
what is a solution?
homogeneous mixture
oxygen element, compound, homogeneous or heterogeneous mixture
homogenous mixture
the solubility of most solids _____ as the temperature increases
increases
what is a word that means "to repeat according to some pattern"?
periodic
what is the right side of a chemical equation?
product
what is each element composed of?
protons, neutrons, electrons
what is the left side of a chemical equation?
reactant
which of the following is a chemical property? density, color, boiling point, reactivity with acid
reactivity with acid
what is the sugar in sweetened ice tea called? what is the water?
solute solvent
what are the three types of mixtures?
solutions, colloids, suspension
give an example of solution, colloid, suspension
sprite, mayo, dressing
which of the following is NOT a sign of chemical reaction?
state change
what are the medicines that instruct you to shake the bottle well before use?
suspensions
what happens to atoms in a chemical reaction?
they are never lost or gained, just rearranged
which of the following does NOT describe elements? they can join together to form compounds, they have unique sets of properties, they can be broken down into simpler substances, they are represented by symbols
they can be broken down into simpler substances
molecules
two or more atoms bonded together
compound
two or more different kinds of atoms bonded together
isotopes
2 atoms of the same element with different masses
T/F the components in a mixture do not combine chemically
T
T/F water is a common compound on Earth
T
sodium is a soft, silvery metal that reacts violently with water. chlorine is a poisonous, greenish yellow gas. when you combine these two elements you form a soluble white solid this is soluble in water and safe to eat
a compound has different properties from the elements that form it
what happens when two or more elements join together chemically?
a compound is formed
how can you be sure a chemical reaction is happening?
a new substance is formed
what is matter?
anything that has mass and volume
what is the smallest particle in which an element can be divided and still be the same substance?
atom
what is the elements arranged in order of increasing in the modern periodic table?
atomic number
how is the modern table organized?
by atomic number
what is an element?
can't be broken down by chemical means
what is the force that holds two atoms together called?
chemical bond
caffeine element, compound, homogeneous or heterogeneous mixture
compound
most metals are good _____ of thermal energy ex: frying pan
conductors
how could a sugar cube be dissolved more quickly in water?
crush the sugar cube
how is a compound different from a mixture?
each substance in a compound loses its characteristic properties
what has a negative charge and a mass almost equal to zero?
electron
what is made up of one kind of atom?
element
which of the following is an example of a chemical reaction? ice melting in a glass of water, paper turning soft when wet, salt crystals forming as sea water evaporates, leaves changing colors in the fall
leaves changing colors in the fall
which of the following states the law of conservation of mass?
mass cannot be created nor destroyed in a chemical reaction
what is an element that conducts thermal energy well and is easily shaped?
metal
what are the elements to the right of the zigzag line on the periodic table?
metalloids
what are the three major categories of elements?
metals, nonmetals and metalloids
which of the following best describes chicken noodle soup? element, compound, mixture, solution
mixture
most matter exists as ____
mixtures
what are most natural substances?
mixtures
what causes chemical bonds in molecules to break?
molecules bump into each other with enough energy to break them