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MUS science exam rev
science mus
Question | Answer |
---|---|
the smallest unit of the element that keeps the same properties of the element | atom |
an atoms central region, which is made up of protons and neutrons | nucleus |
a region around the nucleus of an atom where electrons are likely to be found | electron cloud |
Who thought that matter was composed of atoms | Democritus |
Who based his theory on observations of how elements combine | Dalton |
Who discovered electrons in an atom | Thompson |
Who discovered that atoms are mostly empty space with a dense, positive nucleus | Rutherford |
Who proposed that electrons are located in levels at certain distances from the nucleus | Bohr |
a subatomic particle that has a positive charge and is found in the nucleus of an atom | proton |
a unit of mass that describes the mass of an atom or molecule | atomic mass unit |
a subatomic particle that has no charge and is found in the nucleus of an atom | neutron |
What are found in all atoms? | Protons and Electrons |
the number of protons in the nucleus of the atom; the atomic number is the same for all atoms of an element | atomic number |
an atom that has the same number of protons of other atoms of the same element do but that has a different number of neutrons (and thus a different atomic number) | isotope |
the sum of the numbers of protons and neutrons in the nucleus of an atom | mass number |
the mass of an atom expressed in atomic mass units | atomic mass |
ordindary-sized objects are made up of very large numbers of atoms | atoms are extremely small |
What consist of a nucleus, which has protons and usually neutrons, and electrons, located in electron clouds around the nucleus? | Atoms |
What is the number of protons in the nucleus of a atom? | atomic number |
All atoms of an element have the same what? | atomic number |
Different isotopes of an element have... | different numbers of neutrons in their nuclei. |
Isotopes of an element share... | most chemical and physical properties |
The mass of an atom is... | the sum of the atom's neutrons and protons |
What is a weighted average of the masses of natural isotopes of an element? | Atomic mass |
What are the forces at work in an atom? | gravitational force, electromagnetic force, strong force, and weak force. |
something that occurs or repeats at regular intervals | periodic |
the law that states that the repeating chemical and physical properties of elements change periodically with the atomic numbers of the elements | periodic law |
what are four properties shared by most metals | solid at room temperature, ductile, malleable, and shiny. most are good conductors or electric currents and thermal energy. |
properties of nonmetal | not malleable or ductile, not shiny and are poor conductors of thermal energy and electric currents |
properties of metals | shiny, ductile, good conductors of electric currents, malleable, and good conductors of thermal energy |
properties of metalloids | shiny, brittle, & good conductor of electric currents |
a horizontal row of elements in the periodic table | period |
a vertical column of elements in the periodic table; elements in a group share chemical properties | group |
how did Mendeleev develop the first periodic table? | by listing the elements in order of increasing atomic mass |
properties of what repeat in a regular, or periodic pattern | properties of elements |
one of the elements of group one on the periodic table | Alkali Metals |
one of the elements on group two on the periodic table | alkaline-earth metals |
why are alkali metals more reactive than transition metals | it is easier for alkali metals to loose their outer shell of electrons than for transition metals |
the hardest material known | diamond |
formed from burning oil, coal, and wood and is used as a pigment in paints and crayons | soot |
all of the elements of group 18 of the periodic table; | are unreactive |
what are four properties shared by most metals | solid at room temperature, ductile, malleable, and shiny. most are good conductors or electric currents and thermal energy. |
a horizontal row of elements in the periodic table | period |
a vertical column of elements in the periodic table; elements in a group share chemical properties | group |
how did Mendeleev develop the first periodic table? | by listing the elements in order of increasing atomic mass |
properties of what repeat in a regular, or periodic pattern | properties of elements |
why are alkali metals more reactive than transition metals | it is easier for alkali metals to loose their outer shell of electrons than for transition metals |
the hardest material known | diamond |
formed from burning oil, coal, and wood and is used as a pigment in paints and crayons | soot |
what are four properties shared by most metals | solid at room temperature, ductile, malleable, and shiny. most are good conductors or electric currents and thermal energy. |
properties of nonmetal | not malleable or ductile, not shiny and are poor conductors of thermal energy and electric currents |
properties of metals | shiny, ductile, good conductors of electric currents, malleable, and good conductors of thermal energy |
properties of metalloids | shiny, brittle, & good conductor of electric currents |
a horizontal row of elements in the periodic table | period |
a vertical column of elements in the periodic table; elements in a group share chemical properties | group |
how did Mendeleev develop the first periodic table? | by listing the elements in order of increasing atomic mass |
properties of what repeat in a regular, or periodic pattern | properties of elements |
why are alkali metals more reactive than transition metals | it is easier for alkali metals to loose their outer shell of electrons than for transition metals |
the hardest material known | diamond |
formed from burning oil, coal, and wood and is used as a pigment in paints and crayons | soot |
one of the elements of group seven-teen of the periodic table | halogen |
what are four properties shared by most metals | solid at room temperature, ductile, malleable, and shiny. most are good conductors or electric currents and thermal energy. |
properties of nonmetal | not malleable or ductile, not shiny and are poor conductors of thermal energy and electric currents |
properties of metals | shiny, ductile, good conductors of electric currents, malleable, and good conductors of thermal energy |
properties of metalloids | shiny, brittle, & good conductor of electric currents |
a horizontal row of elements in the periodic table | period |
a vertical column of elements in the periodic table; elements in a group share chemical properties | group |
how did Mendeleev develop the first periodic table? | by listing the elements in order of increasing atomic mass |
properties of what repeat in a regular, or periodic pattern | properties of elements |
why are alkali metals more reactive than transition metals | it is easier for alkali metals to loose their outer shell of electrons than for transition metals |
the hardest material known | Diamond |
formed from burning oil, coal, and wood and is used as a pigment in paints and crayons | Soot |
what are four properties shared by most metals | solid at room temperature, ductile, malleable, and shiny. most are good conductors or electric currents and thermal energy. |
properties of nonmetal | not malleable or ductile, not shiny and are poor conductors of thermal energy and electric currents |
properties of metals | shiny, ductile, good conductors of electric currents, malleable, and good conductors of thermal energy |
properties of metalloids | shiny, brittle, & good conductor of electric currents |
a horizontal row of elements in the periodic table | period |
a vertical column of elements in the periodic table; elements in a group share chemical properties | group |
how did Mendeleev develop the first periodic table? | by listing the elements in order of increasing atomic mass |
properties of what repeat in a regular, or periodic pattern | properties of elements |
one of the elements of group one on the periodic table | Alkali Metals |
one of the elements on group two on the periodic table | alkaline-earth metals |
why are alkali metals more reactive than transition metals | it is easier for alkali metals to loose their outer shell of electrons than for transition metals |
the hardest material known | diamond |
formed from burning oil, coal, and wood and is used as a pigment in paints and crayons | soot |
what are four properties shared by most metals | solid at room temperature, ductile, malleable, and shiny. most are good conductors or electric currents and thermal energy. |
properties of nonmetal | not malleable or ductile, not shiny and are poor conductors of thermal energy and electric currents |
properties of metals | shiny, ductile, good conductors of electric currents, malleable, and good conductors of thermal energy |
properties of metalloids | shiny, brittle, & good conductor of electric currents |
a horizontal row of elements in the periodic table | period |
a vertical column of elements in the periodic table; elements in a group share chemical properties | group |
how did Mendeleev develop the first periodic table? | by listing the elements in order of increasing atomic mass |
properties of what repeat in a regular, or periodic pattern | properties of elements |
why are alkali metals more reactive than transition metals | it is easier for alkali metals to loose their outer shell of electrons than for transition metals |
the hardest material known | Diamond |
formed from burning oil, coal, and wood and is used as a pigment in paints and crayons | Soot |
why are noble gases unreactive | they have a full set of valence electrons |
which are the most reactive metals | alkali metals |
which metals are less reactive than alkali | alkaline-earth metals |
which metals include most of the well known metals | transition metals |
what force pulls objects together such as the sun, earth; cars | gravitational force |
what force holds electrons around the nucleus | electromagnetic force |
what is the force that makes protons push away form one another | strong force |
what force is important in radioactive elements | the weak force |
a subatomic particle that has a negative charge | electron |
an atom that has the same # of protons as other atoms of the same element but has a different # of neutrons | isotope |
radioactive | weak force |
the joining of atoms to form new substances | chemical bonds |
atoms strive to achieve a full set of valence electrons(8 valence electrons) | octet rule |
metals will lose electrons | true |
nonmetals will gain electrons | true |
what will decide whether or not to bond | valence electrons |
a solid that is produced as a chemical reaction | precipitate |
what is the most important sign of a chemical reaction taking place | the formation of substances that have different properties |
if molecules bump into each-other with enough force, what will happen | the chemical bonds will break |
what is the process by which substances change to produce new substances with new chemical and physical properties | a chemical reaction |
what do particles do in a solid | they vibrate in place |
what has fast moving particles | a gas |
what happens to the particles in an object at higher temperatures | they move faster |
why can balloons be twisted into different shapes | because the particles of gas can be compressed |
what happens to the particles of gas when a liquid becomes a gas | they break away from each other |
according to Charles' law, crushing a closed container of gas will make what happen | the pressure will increase |
if you open a bottle of perfume, after a while the smell will get to the other side of the room. what property is this | sublimation |
the melting point of salt is the same as its what | freezing point |
the point at which a liquid becomes a gas | vapor point |
how would you describe the nucleus | dense and positively charged |
when was Dalton's theory changed | 1800's |
all isotopes have the same number of what | protons |
what physical property are most metals at room temperature | solid |
how did Mendeleev arrange the elements on the periodic table | by increasing atomic mass |
mercury is the only transition metal that is not what at room temperature | solid |
what did Thompson discover that are negatively charged particles | electrons |