physical science midterm 1 Flashcards
1
Q
A recording of the substance that produces hydrogen ions in a water solution. The level of acid in substances.
A
Acidity
2
Q
They are found in group IA. The elements within this chemical family have one valence electron that is easily lost.
A
Alkali Metals
3
Q
They are found in group IIA. The elements within this chemical family have two valence electrons that can be readily lost.
A
Alkaline Earth Metals
4
Q
A particle consisting of two protons and two neutrons that is emitted from a decaying atomic nucleus.
A
Alpha Particle
5
Q
smallest unit into which matter can be divided without the release of electrically charged particles. It also is the smallest unit of matter that has the characteristic properties of a chemical element. Particles that makeup matter that are too small to see are known as ____. ____ are composed of mostly empty space. The nucleus of a(n) ___ contains protons and neutrons. The negatively charged particle outside the nucleus is the electron.
A
Atom
6
Q
the number at the top of each element box, is the number of protons in the nucleus and the number of electrons in the atom.
A
Atomic Number
7
Q
The average _____, sometimes called atomic weight, of an element is the weighted average mass of the atoms in a naturally occurring sample of the element. Average masses are generally shown in unified atomic mass units (u), where 1 u is equal to exactly one-twelfth the mass of a neutral atom of carbon-12.
A
Atomic Mass
8
Q
A chemical equation with the same number of each element on both sides of the equation.
A
Balanced Chemical Equation
9
Q
High energy electron that is emitted when a neutron decays into a proton.
A
Beta Particle
10
Q
A compound that is composed of two elements.
A
Binary Compound
11
Q
This is a gas law which states that the pressure exerted by a gas (of a given mass, kept at a constant temperature) is inversely proportional to the volume occupied by it. In other words, the pressure and volume of a gas are inversely proportional to each other as long as the temperature and the quantity of gas are kept constant. _____ was put forward by the Anglo-Irish chemist Robert Boyle in the year 1662.
A
Boyle’s Law
12
Q
This is the scattering of a beam of light by a medium containing small suspended particles. For example smoke or dust in a room, which makes visible a light beam entering a window.
A
Tyndall Effect
13
Q
________ are members of the actinide series beyond uranium, beginning with neptunium/ atomic number 93. These are artificially produced in nuclear reactors, accelerators, or explosions of nuclear weapons.
A
Transuranium Element
14
Q
A process of changing one element to another through radioactive decay.
A
Transmutation
15
Q
____ are elements that have partially filled subshell partially filled with electrons, or an element that has the ability to form stable cations with an incompletely filled orbital. In general, any element of groups 3-12 is considered to be a _____. The lanthanides and the actinides can be considered as transition metals.
A
Transition Elements
16
Q
A radioactive isotope such as iodine 131 that can be detected by the radiation it emits after it is absorbed by a living organism.
A
Tracer
17
Q
the general increase in the volume of a material as its temperature is increased. It is usually expressed as a fractional change in length or volume per unit temperature change.
A
Thermal Expansion
18
Q
Thermal energy is the total energy of the motion of the particles in an object. Thermal energy flows from warmer matter to cooler matter. The greater the energy of the particles in the warmer parts of the material transferred to the particles in the cooler parts. The transfer of thermal energy is known as heat. Metals conduct thermal energy easily because the valence electrons within a metal are free to move. Electrons in the warmer part of the metal can transfer energy to electrons in the cooler part of the metal.
A
Thermal Conductivity
19
Q
A chemical reaction in which two or more substances combine to form a different substance.
A
Synthesis reaction
20
Q
The elemental symbol is an abbreviation of the element name. Some periodic tables do not include the element names, only the symbols.
A
Symbol
21
Q
a type of matter with a fixed composition. ________ is made up of only one form of atom is an element.
A
Substance
22
Q
This is a conversion of a substance from the solid to the gaseous state without its becoming liquid. An example is the vaporization of frozen carbon dioxide (dry ice) at ordinary atmospheric pressure and temperature.
A
Sublimation
23
Q
An attractive force that acts between protons and neutrons in an atomic nucleus.
A
Strong force
24
Q
The part of the solution usually present in the largest amount.
A
Solvent
25
this is the same thing as a homogeneous mixture. Some might be solids dissolved in liquids, but they can also be solid and gas, solid and solid, and gas and liquid, etc. a special kind of mixture that has 2 phases/parts. It contains a solvent and at least one solute and it has the same properties throughout.
Solution
26
The substance that is dissolved.
Solute
27
is defined as the maximum amount of a substance that will dissolve in a given amount of solvent at a specified temperature. _____ is a characteristic property of a specific solute–solvent combination, ______ is a characteristic property of a specific solute/solvent combination, and different substances have varying ____________.
Solubility
28
A chemical reaction in which one element replaces another element in a compound.
Single-displacement reaction
29
NaCl (table salt) Salt is a substance that results in the formation of a neutralization reaction of acids and bases.
Salt
30
A reaction that can proceed in both the forward and the reverse directions.
Reversible Reaction
31
The gain of electrons by the atoms of a substance in a chemical reaction.
Reduction
32
The ability to react. The degree to which a substance shows chemical change when mixed with another substance. It is a measurement of how much a substance reacts with others.
Reactivity
33
The rate at which reactants change into products in chemical reaction.
Reaction Rate
34
The lanthanide series and the actinide series, located at the bottom of the periodic table, are the inner transition metals (the ______ metals).
Rare Earth Metals
35
A process that occurs when a nucleus decays and emits matter and energy.
Radioactivity
36
_______ are made up of atoms whose nuclei are unstable and give off atomic radiation as part of a process of attaining stability. The common 4 radioactive elements are Uranium, Radium, Polonium, and Thorium. All elements can have radioactive isotopes. If enough neutrons are added to an atom, it becomes unstable and decays. Each element is followed by the most stable known isotope and its half-life.
Radioactive Element
37
Scientists infer that protons and neutrons (not electrons) are composed of smaller particles.
Quark
38
Particles in the nucleus of an atom with an electric charge of 1+.
Proton
39
In a chemical reaction, the new substances formed.
Products
40
The burning of logs in a fireplace is the reaction of the wood and oxygen along with a heat initiation source. When this reaction occurs, a large amount of energy is produced. This energy is in the form of both heat and light. This type of reaction is a combustion reaction.
Production Of Light
41
Mixing antacids with water creates the gas carbon dioxide. Anytime molecules rearrange to form a gas as a byproduct of a chemical reaction, you can be sure that a chemical change has occurred.
Production of a Gas
42
This is a positively or negatively charged covalently bonded group of atoms.
Polyatomic ion
43
A neutral molecule in which unequal electron sharing results in a positive end and a slightly negative end.
Polar molecule
44
A covalent bond in which the electrons are not shared equally. This results in a slightly positive and slightly negative end. You can predict whether or not molecules will mix together to form chemical solutions. The general rule is that "like dissolves like", which means polar molecules will dissolve into other polar liquids.
Polar bond
45
In physics, it contains a significant portion of charged particles (ions) and/or electrons. The presence of these charged particles is what primarily sets _______ apart from the other fundamental states of matter. It is the most abundant form of ordinary matter in the universe (stars.)
Plasma
46
_______ is a characteristic of matter that is not associated with a change in its chemical composition. Examples include density, color, hardness, melting and boiling points, and thermal conductivity. ___________ of matter include properties that describe the substance, such as color, smell, boiling point, and density.
Physical Property
47
This is a table that organizes all discovered chemical elements in rows (called periods) and columns (called groups) according to increasing atomic number. Scientists use the _______ to quickly refer to information about an element, like atomic mass and chemical symbol.
Periodic Table
48
Rows are called _______ in the Periodic Table. The number of valence electrons increases from left to right, beginning with 1 and ending with 8. (Except row 1, helium has 2.)
Period
49
This is the positive or negative number that indicates how many electrons an atom has gained, lost, or shared to make it stable.
Oxidation number
50
The loss of electrons from the atoms of a substance in a chemical reaction. Chemical reactions of this type often involve oxygen. Oxygen is very reactive and it pulls electrons from metallic elements. The substance that loses an electron and becomes positive is oxidized.
Oxidation
51
The ____ rule is that an atom will be most stable when surrounded by 8 electrons in the valence shell. An atom that does not have eight electrons will bond with other atoms to have eight electrons
Octet
52
the small positively charged center of an atom containing protons and neutrons. Protons and neutrons are almost 2000 times as massive as electrons. The atoms of an element all have the same number of protons in heir nucleus.
Nucleus
53
Molecules that share electrons equally and do not have oppositely charged ends.
Nonpolar molecule
54
A covalent bond in which electrons are shared equally by both atoms. It does not have oppositely charged ends.
Nonpolar bond
55
__________ generally possess the following properties: They do not give up electrons easily. They form ionic compounds or polar covalent compounds when reacting with metals and have relatively low boiling points. They are poor conductors of heat and electricity (insulators). _______ are at the right end of the Periodic Table of Elements and have an almost complete set of electrons in their outer level and more than half are gas at room temperature.
Nonmetals
56
_________ are found in group VIIIA. The ________ have the maximum number of valence electrons (two for helium and an octet of, or eight, valence electrons for all other ________), so they have little tendency to gain or lose electrons and are non-reactive.
Noble Gasses
57
are electrically charged particles in the nucleus and they do NOT have a charge.
Neutrons
58
A neutral particle that forms as a result of electron sharing among atoms. _______ is a substance of different kinds of atoms joined together. An example is water, H2O.
Molecule
59
This is a counting unit in chemistry. The number of particles is so large that a counting unit helps. The amount of substance that contains 6.02 x 1023 particles of that substance. The number of atoms or other particles in a mole is the same for all substances. In comparison, one mole of oxygen consists, by definition, of the same number of atoms as carbon-12, but it has a mass of 15.999 grams. (One mole of carbon-12 atoms has 6.02214076 × 1023 atoms and a mass of 12 grams.) Oxygen, therefore, has a greater mass than carbon.
Mole
60
______ The mass in grams of one mole of a substance.
_____ is of importance when setting up an experiment. If you are testing principles involving specific amounts of a substance, the molar mass allows you to figure out how much you should weigh out on your scale. M = m/n
M = molar mass; m = mass of substance in grams; n = number of moles
Molar mass
61
Contains at least 2 PHYSICALLY combined compounds; can be homogeneous or heterogeneous.
Mixture
62
Most elements are metals and are solid at room temperature. Metals conduct electric current easily because the valence electrons in a metal can move freely among the atoms. Metals conduct thermal energy easily because the valence electrons within a metal are free to move.
Metals
63
This is used to describe a chemical element that forms a simple substance having properties intermediate between those of a typical metal and a typical nonmetal. They are a simple substance having properties intermediate between those of a typical metal and a typical nonmetal. ______ that can conduct electricity at higher temperatures are called semiconductors.
Metalloid
64
_________ are the chemical bonds that hold atoms together in metals. They differ from covalent and ionic bonds because the electrons in metallic bonding are not shared between only two atoms. The electrons in metallic bonds float freely. This type of bonding gives metals many unique material properties, including thermal and electrical conductivity, high melting points, and malleability.
Metallic Bonding
65
You can use characteristic physical and chemical properties to compare and classify _______. The ability to burn is a chemical property.
Matter
66
The ________ is the number of protons and the number of neutrons in an atom. If you want to calculate how many neutrons an atom has, you can simply subtract the number of protons, or atomic number, from the mass number.
Mass Number
67
_________ is similar to ductility. Refers to a metal's capacity for thinning and lateral (from the side) expansion. Deformation under compressive stress. They can be rolled into thin sheets, as with aluminum foil. Metals can be beaten into complex shapes. Examples of malleable metals are gold, iron, aluminum, copper, silver, and lead.
Malleable/Malleability
68
Polished metals have a shiny, reflective ______, called metallic ____. The luster of metal is due to its valence electrons. When light strikes the electrons, they absorb the light and then re-emit the light. ______ is the way light interacts with the surface of a crystal, rock, or mineral. The word traces its origins back to the Latin lux, meaning "light", and generally implies radiance, gloss, or brilliance.
Luster
69
When liquids boil the particles must have sufficient energy to break away from the liquid and to diffuse through the surrounding air particles. As these particles cool down and lose energy they will condense and turn back to liquid.
Liquids
70
This states that if stress is applied to a system at equilibrium, the equilibrium shifts in the direction that opposes the stress. Common stresses that do that are changing the concentration by adding or removing a reactant or product, changing the temperature by adding or removing heat, and changing the volume and pressure.
Le Chatelier's principle
71
states that the mass of all substances present before a chemical change equals the mass of all the remaining substances after the change.
Law of Conservation of Mass
72
states that matter is composed of a large number of small particles (individual atoms or molecules) that are in constant motion. It assumes that particles are small and widely separated and they collide and exchange energy. It helps explain the flow or transfer of heat and the relationship between pressure, temperature and volume properties of gasses.
Kinetic Theory
73
Atoms of the same element that have different numbers of neutrons. i.e. Carbon 12 has 6 protons and neutrons. Carbon 14 has 6 protons and eight neutrons
Isotope
74
The force of attraction between the opposite charges of the ions in an _______.The result of _______ is a neutral compound. The sum of the charges is zero. When an atom forms an ionic compound the electrons are shifted between the two atoms, but the overall number of protons and neutrons remains unchanged. ______ is when oppositely charged electrons attract and a neutral atom loses a valence electron.
Ionic Bond
75
A charge particle that has either more or fewer electrons than protons. Many normal substances exist in the body as _____. Common examples include sodium, potassium, calcium, chloride, and bicarbonate. These substances are known as electrolytes. _____ can be created using radiation such as x-rays. Positive _____ are typically metals or act like metals.
Ion
76
This is a substance that slows down a chemical reaction or prevents it from occurring by combining with a reactant. An example of an _________ is a food preservative that helps prevent food from spoiling.
Inhibitor
77
A compound that has water chemically attached to its atoms and written into its chemical formula. These have water molecules as part of their structures. It is a compound with extra water molecules that are part of its structure. These water molecules have been absorbed from its environment. Some common hydrates are listed here as information only:
Hydrate
78
a mixture that remains constantly and uniformly mixes and has particles that are so small they cannot be seen with a microscope.
Homogeneous
79
this is a mixture in which different materials remain distinct
Heterogeneous Mixture
80
is defined as the amount of heat needed to turn 1 g of a liquid into a vapor, without a rise in the temperature of the liquid.
Heat of Vaporization
81
is the quantity of heat necessary to change 1 g of a solid to a liquid with no temperature change. Solids can be heated to the point where the molecules holding their bonds together break apart and form a liquid. The most common example is solid ice turning into liquid water. Balance between temperature and pressure intra and intermolecular forces - molecules organized or unorganized. I.e. chemical bonds may be broken or less closely packed together. (release/ gain energy)
Heat of Fusion
82
The ____ are nonmetals found in group VIIA of the periodic table. The elements within this chemical family are highly reactive, as they have seven valence electrons.
Halogen
83
The amount of time it takes for half the nuclei in a sample of radioactive isotope to decay.
Half-life
84
The elements in each ________ have the same number of valence electrons. As a result, elements in the same ________- often display similar properties and reactivity. For example, carbon has 4 valence electrons. Columns are called _______ in the Periodic Table.
Groups
85
A _________ is a solid substance that forms and separates from a solution. A ________ often settles to the bottom of a liquid reaction.
Formation of a Precipitate
86
A chemical in which energy is primarily given off in the form of thermal energy. Examples include wood burning and dynamite being exploded. These reactions produce most of the power used in homes and industries.
Exothermic Reaction
87
This is a chemical reaction that releases some form of energy, such as light or thermal energy.The energy to activate the original bonds is less than the energy to release when new bonds are formed. An example of this is a firefly producing light in their abdomen.
Exergonic Reaction
88
A state in which forward and reverse reactions or processes occur at equal rates.This is a state of balance or equilibrium. When a chemical reaction takes place in a closed system which prevents the input or removal of any of the components involved in the reaction, the quantities of these chemicals change as some are consumed and others are formed. Eventually this change will stop, after which the reaction composition will remain unchanged as long as the system is not disturbed. A chemical reaction is in equilibrium when there is no tendency for the quantities of reactants and products to change.
Equilibrium
89
A chemical reaction that requires thermal energy in order to proceed. _________ can be chemical changes, but also physical. An example is when you mix water H2O with Epson salt. In this reaction, the solution becomes cold. This dissolving absorbs thermal energy and that is a physical change.
Endothermic Reaction
90
Chemical reaction that requires energy input in the form of light, thermal energy or electricity in order to proceed. Sometimes a reaction requires more energy to break bonds than is released when new ones are formed.. Electricity is often used to supply energy to ____________.
Endergonic Reaction
91
A substance made up of only one form of atom is an ________. An ________ is any substance that cannot be decomposed into simpler substances by ordinary chemical processes. ________ are the fundamental materials of which all matter is composed. Most __________ are metal and are solid at room temperature.
Element
92
particles with an electric charge of 1- and they occupy the space surrounding the nucleus of the atom.
Electrons
93
This is a representation of the valence electrons of an atom that uses dots around the symbol of the element. The number of dots equals the number of valence electrons in the atom. These dots are arranged to the right and left and above and below the symbol, with no more than two dots on a side. (It does not matter what order the positions are used.)
Electron Dot Diagram
94
It is described as a region with a high probability of containing electrons. An ____________ is the region of negative charge surrounding an atomic nucleus that is associated with an atomic orbital.
Electron Cloud
95
Charged particles that are free to move can conduct an electric current. Metals conduct electric current easily because the valence electrons in a metal can move freely among the atoms. Electrical wires are made out of metal. Circuit boards contain metal strips that conduct electrical current throughout the circuit.
Electrical Conductivity
96
________ is similar to malleability. A metal's capacity for elongation and/or reduction of cross-sectional area under tension, i.e., pulling in one direction. They can be pressed permanently out of shape without breaking or cracking. A mechanical property that describes the extent in which solid materials can be plastically deformed without fracture. Often characterized by the material's ability to be stretched into a wire.
Ductile/Ductility
97
A reaction in which two ionic compounds in solution are combined and can produce a precipitate, water or a gas. (see precipitate)
Double-displacement Reaction
98
refers to the selective boiling and subsequent condensation of a component in a liquid mixture. It is a separation technique that can be used to either increase the concentration of a particular component in the mixture or to obtain (almost) pure components from the mixture.
Distillation
99
The 7 diatomic elements are hydrogen (H), nitrogen (N), oxygen (O), fluorine (F), chlorine (Cl), bromine (Br), and iodine (I). Any of the homonuclear diatomic elements: H2, N2, O2, Cl2. A diatomic element is a molecule composed of two of the same atom. The word diatomic comes from ‘di’ meaning two, and ‘atomic’ meaning atom. NOTE: A monatomic element is stable with just one atom. Diatomic elements are most stable in this paired form because it allows them to follow the octet rule.
Diatomic molecule
100
A chemical reaction in which one substance breaks down into two or more substances.
Decomposition Reaction
101
These form from nonmetallic elements. Some atoms of nonmetals are unlikely to gain or lose electrons because it would take a great deal of energy. Each time an electron is removed the nucleus holds those remaining more tightly. Thos atoms become more stable by sharing rather than becoming ions. The neutral particle that forms is known as a MOLECULE.
Covalent Bond
102
Is a substance formed when two or more chemical elements are chemically bonded together.
Compound
103
The chemical reaction that occurs when a substance reacts with oxygen to produce energy in the form of heat and light.
Combustion Reaction
104
Note: Antoine Lavoisier, known as the father of modern chemistry, is most noted for his discovery of the role oxygen plays in combustion. He deduced that the process of burning (combustion) involves the combination of a substance with oxygen. He recognized and named oxygen (1778) and hydrogen (1783). Lavoisier helped construct the metric system, wrote the first extensive list of elements, and helped to reform chemical nomenclature.
Combustion
105
This states hat atoms, ions, and molecules must collide in order to react. Chemists use this idea to explain why reaction rates depend upon temperature and other factors, such as concentration and surface area. For example lowering the temperature decreases the rate of chemical reactions that cause spoilage and increasing generally increases it.
Collision Model
106
The number in a chemical equation that represents the number of units of each substance taking part in a chemical reaction. For example, two molecules of hydrogen would be written as 2H2. A coefficient of 1 usually isn't written.
Coefficient
107
The process in which one or more substances are changed into new substances.
Chemical Reaction
108
Chemical properties of matter describes its potential to undergo some chemical change or reaction by virtue of its composition.
Chemical Property
109
____ of matter include all the possible chemical changes that a sample of matter can undergo, such as oxidation resistance (ability to resist corrosion), toxicity (the degree to which a substance is poisonous to an organism or the environment), and heat of combustion (amount of heat released when a substance is burned).
Chemical properties
110
Chemical shorthand that uses symbols to tell what elements are in a compound and their ratios.
Chemical formula
111
A shorthand method of describing chemical reactions using chemical formulas and other symbols.
Chemical Equation
112
is a process in which one or more substances are altered into one or more new and different substances. In other words, a chemical change is a chemical reaction involving the rearrangement of atoms.Chemical change to matter will always result in the formation of a new substance.
Chemical Change
113
A _________ is a force of attraction that holds 2 atoms together as a result of the arrangement of electrons between them. _________ form when 2 atoms share electrons is a covalent bond.
Chemical Bond
114
The volume of the gas increases with increasing pressure, as long as the temperature of the gas does not change. ________ is a gas law that states gasses expand when heated. The law is also known as the law of volumes. The law takes its name from French scientist and inventor Jacques Charles, who formulated it in the 1780s. _________ is an ideal gas law where at constant pressure, the volume of an ideal gas is directly proportional to its absolute temperature. The simplest statement of the law is V/T = k where V is volume, T is absolute temperature, and k is a constant.
Charles's Law
115
Chemical reactions can either give off heat or use heat. Temperature changes are evidence of a chemical reaction.
Change in Temperature
116
You may have seen rust form on a steel object, such as a chain or an automobile. The properties of steel are different from the properties of rust. Steel is a shiny, silver metal made from iron and other elements. Rust is a flaky, reddish-colored substance. The change in color from silver to red provides evidence that a chemical reaction has happened. Rusting is a complex reaction that happens in stages, and it is easy to observe these changes as they happen.
Change in Color
117
A substance that speeds up chemical reaction without being permanently changed itself.
Catalyst
118
A series of fission reactions caused by the release of additional neutrons in every step.
Chain reaction
