Chemistry Chapter 2 review
atomos is a term derived from the Greek word for
indivisible
Metals and nonmetals generally form ______ compounds
ionic
When electrons are transferred, ions form, and an _______ bond results
ionic
The gain or loss of electrons forms
ions
Atoms of the same element that differ in mas
isotopes
When a nonmetal forms two oxyanions and the ion has the smaller number of oxygen atoms, what suffix is used
ite
Are shiny, malleable, good conductors of heat and electricity
metals
Name the following compounds: (a) CsCl (b) BaO (c) K2S (d) BeCl2
(a) cesium chloride; (b) barium oxide (c) potassium sulfide; (d) beryllium chloride;
Name the following covalent compounds: (a) SF6 (b) N2O3 (c) Cl2O7
(a) sulfur hexafluoride (b) dinitrogen trioxide (c) dichlorine heptoxide
What are the 5 postulates of Dalton's Atomic Theory?
1. Matter is composed of atoms 2. Elements consists of only one type of atom 3. atoms of one element differ in properties from atoms of all other elements 4. a compound consists of atoms of 2 or more elements combined in a small whole number ratio 5. Atoms are neither created nor destroyed but rearrange to yield a different type of matter
Group 2 on periodic table
Alkaline Earth Metals
What is the molecular and empirical formula for benzene
C6H6- molecular CH- empirical
Group 16 on periodic table
Chalcogens
____________is widely credited with creating the first periodic table of the elements
Dimitri Mendeleev
What are the bottom two rows or periodic table called
Lanthanides: top row • Actinides: bottom row
Any atom that contains six protons is the element carbon and has the atomic number 6, regardless of how many neutrons or electrons it may has T/F
T
Ionic compounds are electrically neutral overall. T/F
T
Most elements exist naturally as a mixture of two or more isotopes. T/F
T
What is the Periodic law
The properties of the elements are periodic functions of their atomic number
CH4 a. molecular formula b. structural formula
a. molecular formula
____________ occupy almost all of an atom's volume
electrons
Write the symbol for each of the following ions: (a) the ion with a 1+ charge, atomic number 55, and mass number 133 (b) the ion with 54 electrons, 53 protons, and 74 neutrons
(a) 133Cs+ (b) 127I−
For each of the following pairs of ions, write the formula of the compound they will form: (a) Ca2+, S2− (b) NH4 + , SO4 2−
(a) CaS; (b) (NH4)2CO3;
Write the formulas of the following ionic compounds: (a) chromium(III) phosphide (b) mercury(II) sulfide (c) manganese(II) phosphate
(a) CrP; (b) HgS; (c) Mn3(PO4)2;
Using the periodic table, identify the lightest member of each of the following groups: (a) noble gases (b) alkaline earth metals
(a) He; (b) Be
The following are properties of isotopes of two elements that are essential in our diet. Determine the number of protons, neutrons and electrons in each and name them. (a) atomic number 26, mass number 58, charge of 2+ (b) atomic number 53, mass number 127, charge of 1−
(a) Iron, 26 protons, 24 electrons, and 32 neutrons; (b) iodine, 53 protons, 54 electrons, and 74 neutrons
The following ionic compounds are found in common household products. Write the formulas for each compound: (a) potassium phosphate (b) copper(II) sulfate
(a) K3PO4; (b) CuSO4
Write the formulas for the following compounds: (a) phosphorus pentachloride (b) dinitrogen monoxide
(a) PCl5; (b) N2O; (c) IF7
Each of the following compounds contains a metal that can exhibit more than one ionic charge. Name these compounds: (a) Cr2O3 (b) FeCl2 (c) CrO3
(a) chromium(III) oxide; (b) iron(II) chloride; (c) chromium(VI) oxide;
Using the periodic table, predict whether the following compounds are ionic or covalent: (a) SO2 (b) CaF2 (c) N2H4
(a) molecular; (b) ionic; (c) molecular
How do you name oxyacids?
1. Omit "hydrogen" 2) Start with the root name of the anion 3) Replace -ate with -ic, or -ite with -ous 4) Add "acid"
Calcium has an atomic number of 20. How many electrons would a neutral calcium have? If it lost 2 electrons, what what it be
20 Lose 2 it becomes a Ca 2+ ion and will have same number of electrons as Argon
Write a symbol for each of the following neutral isotopes. Include the atomic number and mass number for each. (a) the alkali metal with 11 protons and a mass number of 23 (b) the noble gas element with 75 neutrons in its nucleus and 54 electrons in the neutral atom
23Na 11 129Xe 54
A sample of magnesium is found to contain 78.70% of 24Mg atoms (mass 23.98 amu), 10.13% of 25Mg atoms (mass 24.99 amu), and 11.17% of 26Mg atoms (mass 25.98 amu). Calculate the average mass of a Mg atom.
24.31 amu
Give the number of protons, electrons, and neutrons in neutral atoms of each of the following isotopes: 7Li 3
3 protons, 3 electrons, 4 neutrons
Naturally occurring copper consists of 63Cu (mass 62.9296 amu) and 65Cu (mass 64.9278 amu), with an average mass of 63.546 amu. What is the percent composition of Cu in terms of these two isotopes?
69.15% Cu-63 and 30.85% Cu-65
Aluminum and carbon react to form an ionic compound. Predict which forms an anion, which forms a cation, and the charges of each ion. Write the symbol for each ion and name them.
Al will form a cation with a charge of 3+: Al3+, an aluminum ion. Carbon will form an anion with a charge of 4−: C4−, a carbide ion.
Law of Definite Proportions states what?
All samples of a pure compound contain the same elements in the same proportion by mass.
If Group 16 gain an electron, it will form a ________ with what charge?
An anion with a 2- char
How does the atomic number indicate the number of electrons in a neutral atom?
B/c number of proton must equal electrons in a neutral atom. The atomic number tells how many protons
If C2H4O2 is the molecular formula for acetic acid what is the empirical formula
CH2O
_____________ is an abbreviation that we use to indicate an element or an atom of an element
Chemical symbol
Who discovered the nucleus of an atom?
Ernest Rutherford
Where are the noble gases located?
Group 18
Group 17 on the periodic table
Halogens (most reactive non-metals)
___________ bonds are electrostatic forces of attraction
Ionic
Metals readily lose electrons—form cation form which compound
Ionic compound
Using the periodic table, predict whether the following chlorides are ionic or covalent: KCl, NCl3, ICl, MgCl2, PCl5, CCl4.
Ionic: KCl, MgCl2; Covalent: NCl3, ICl, PCl5, CCl4
What would FeCl2 and FeCl3 be called
Iron (II) chloride Iron (III) chloride
Who experimented with Cathode Ray Tubes?
JJ Thomson
Who discovered the neutron?
James Chadwick
The concept of atoms was first proposed by the Greek philosophers _______________ and _____________ in the fifth century BC
Leucippus and Democritus
Predict the formula of the ionic compound formed between the lithium ion and the peroxide ion, O2 2− (Hint: Use the periodic table to predict the sign and the charge on the lithium ion.)
Li2O2
Conduct heat and electricity moderately well, and possess some properties of metals and some properties of nonmetals
Metalloids
A molecule of metaldehyde (a pesticide used for snails and slugs) contains 8 carbon atoms, 16 hydrogen atoms, and 4 oxygen atoms. What are the molecular and empirical formulas of metaldehyde?
Molecular formula, C8H16O4; empirical formula, C2H4O
Predict the formula of the ionic compound formed between the sodium cation, Na+, and the sulfide anion, S2−.
Na2S
How do you name hydrates?
Name the anhydrous compound (per usual rules) 2) Add the word hydrate with a Greek prefix denoting the number of water molecule
How do you name ionic compounds?
Name the positive ion (cation) first followed by the negative ion (anion) but drop the end and add "-ide". if it is a polyatomic ion, use the polyatomic ion name.
Group 15 on the periodic table
Pnictogens
are electrically charged molecules (a group of bonded atoms with an overall charge)
Polyatomic ions
When predicting ion charge, moving from left to right on periodic table what happens
Positive charges of cations are equal to the group number
Give the symbol and name for the ion with 34 protons and 36 electrons.
Se2−, the selenide ion
Only the first letter of a chemical symbol is capitalized. T/F
T
Protons and neutrons are much heavier than electrons. T/F
T
Give the group name for the following elements: (a) chlorine (b) calcium (c) sodium (d) sulfur
The family names are as follows: (a) halogen (b) alkaline earth metal (c) alkali metal (d) chalcogen
Molecules of glucose (blood sugar) contain 6 carbon atoms, 12 hydrogen atoms, and 6 oxygen atoms. What are the molecular and empirical formulas of glucose?
The molecular formula is C6H12O6 because one molecule actually contains 6 C, 12 H, and 6 O atoms. The simplest whole-number ratio of C to H to O atoms in glucose is 1:2:1, so the empirical formula is CH2O.
What is the law of conservation of matter?
The total mass of matter present when matter changes from one type to another will remain constant
If Group 1 loses an electron, it will form a ________ with what charge?
a cation with a 1+ charge
When a metal and nonmetal react, what happens?
a transfer of electrons usually takes place.
Determine the empirical formulas for the following compounds: (a) caffeine, C8H10N4O2
a) C4H5N2O
Write the formulas of the following compounds: (a) chlorine dioxide (b) dinitrogen tetraoxide (c) potassium phosphide
a) ClO2; (b) N2O4; (c) K3P
Write the formulas of the following compounds: (a) rubidium bromide (b) magnesium selenide (c) sodium oxide
a) RbBr; (b) MgSe; (c) Na2O
For each of the following compounds, state whether it is ionic or covalent. If it is ionic, write the symbols for the ions involved: (a) NF3 (b) BaO
a) covalent; (b) ionic, Ba2+, O2−
Name the following ionic compounds, which contain a metal that can have more than one ionic charge: (a) Fe2S3 (b) CuSe (c) GaN (d) CrCl3
a) iron(III) sulfide (b) copper(II) selenide (c) gallium(III) nitride (d) chromium(III) chloride
Use the periodic table to give the name and symbol for each of the following elements: (a) the noble gas in the same period as germanium (b) the alkaline earth metal in the same period as selenium
a) krypton, Kr; (b) calcium, Ca
What are the IUPAC names of the following compounds? (a) manganese dioxide (b) mercurous chloride (Hg2Cl2) (c) ferric nitrate [Fe(NO3)3]
a) manganese (IV) oxide: (Mn +4) b) Mercury (1) chloride. (Hg +1) c) Ferric nitrate: Iron (III) nitrate.
Write the molecular and empirical formulas of the following compounds O=C=O
a) molecular CO2, empirical CO2
A neutral oxygen atom (Z = 8) has eight electrons, and if it gains two electrons it will become a(n) _________ with a 2− charge (8 − 10 =2-). a. anion b. cation
a. anion
Group 1 elements except for Hydrogen
alkali metals
If Group 17 gain an electron, it will form a ________ with what charge?
an anion with a 1- charg
An atom that gains one or more electrons will exhibit a negative charge and is called an
anion
When a nonmetal forms two oxyanions and the ion has the larger number of oxygen atoms, what suffix is used
ate
An ________ is the smallest unit of an element that can participate in a chemical change
atom
The number of protons in the nucleus of an atom is its ____________
atomic number (Z)
A modern periodic table arranges the elements in increasing order of their ____________ and groups atoms with similar properties in the same vertical column
atomic numbers
A meteorite found in central Indiana contains traces of the noble gas neon picked up from the solar wind during the meteorite's trip through the solar system. Analysis of a sample of the gas showed that it consisted of 91.84% 20Ne (mass 19.9924 amu), 0.47% 21Ne (mass 20.9940 amu), and 7.69% 22Ne (mass 21.9914 amu). What is the average mass of the neon in the solar wind?
average mass = (0.9184 × 19.9924 amu) + (0.0047 × 20.9940 amu) + (0.0769 × 21.9914 amu) = (18.36 + 0.099 + 1.69) amu = 20.15 amu
Naturally occurring chlorine consists of 35Cl (mass 34.96885 amu) and 37Cl (mass 36.96590 amu), with an average mass of 35.453 amu. What is the percent composition of Cl in terms of these two isotopes?
average mass = (fraction of 35 Cl × mass of 35 Cl) + (fraction of 37 Cl × mass of 37 Cl) x = 0.7576, which means that 1.00 − 0.7576 = 0.2424. Therefore, chlorine consists of 75.76% 35Cl and 24.24% 37Cl.
A neutral sodium atom (Z = 11) has 11 electrons. If this atom loses one electron, it will become a(n) ________ with a 1+ charge (11 − 10 =1+). a. anion b. cation
cation
An atom that loses one or more electrons will exhibit a positive charge and is called an _________
cation
What was Thompson able to calculate
charge to mass ratio of the cathode ray particles. They were lighter than atoms and negatively charged
Molecular compounds are usually formed by what?
combination of nonmetals
When electrons are shared and molecules form, a _________ bond is formed
covalent
What is the cathode ray particle now called?
electron
Charge of an atom = number of protons - number of _______
electrons
What participates in chemical reactions by being gained, lost or shared
electrons
indicates the simplest whole-number ratio of the number of atoms (or ions) in the compound
empirical formula
Aristotle and others believed that matter consisted of various combinations of what four "elements"
fire earth air water
If Group 2 loses an electron, it will form a ________ with what charge?
form a cation with a 2+ charge
Many nonmetals ____ enough electrons to give them the same number of electrons as an atom of the next noble gas a. gain b. lose
gain
The vertical columns on the periodic table are called
groups
Where are the transition metals located on periodic table
groups 3-13
What are the properties of ionic compounds?
high melting and boiling points nonconductive in solid form conductive in molten form
Compound, often ionic, that contains one or more water molecules bound within its crystals
hydrate
What does the law of multiple proportions state?
if two or more different compounds are composed of the same two elements, then the ratio of the masses of the second element combined with a certain mass of the first element is always a ratio of small whole numbers
When the number of protons and electrons are NOT equal, the atom is electrically charged and called an _____
ions
Compounds with the same chemical formula but different molecular structure
isomers
Many main-group metals ______ enough electrons to leave them with the same number of electrons as an atom of the preceding noble gas. a. gain b. lose
lose
How do atoms and molecules acquire a charge
losing and gaining electrons
What are properties of molecular compounds
lower melting points and boiling points and no conduction of electricity when dissolved in water
The total number of protons and neutrons in an atom is called its ___________
mass number (A)
How do you determine the number of neutrons
mass number (A) minus atomic number (Z) A-Z= number of neutrons
The occurrence and natural abundances of isotopes can be experimentally determined using an instrument called a _______________
mass spectrometer
_____________ compounds (covalent compounds) result when atoms share electron
molecular
A representation of a molecule or compound which consists of chemical symbols and subscripts to indicate the number of each type of atom indicates the actual numbers of atoms of each element in a molecule of the compound
molecular formula
When the number of protons equals the number of electrons the atom is considered what?
neutral
Uncharged, subatomic particles with a mass approximately the same as that of proton
neutrons
appear dull, poor conductors of heat and electric
nonmetals
The ___________ contains most of the atom's mass
nucleus
Compounds that contain hydrogen, oxygen, and at least one other element, and are bonded in such a way as to impart acidic properties to the compound
oxyacids
are polyatomic ions that contain one or more oxygen atoms.
oxyanions
When a nonmetal forms more than two oxyanions, what prefixes are
per- (largest number of oxygens) • hypo - (smallest number of oxygens)
The horizontal rows of the periodic table are called
periods or series
What happens to the nucleus of each atom in chemical reactions
remains unchanged
What would Na2O be
sodium oxide
shows the same information as a molecular formula but also shows how the atoms are connected
structural formula
Each proton and each neutron has a mass of ___________
~ 1 amu
