Chem 101 Chp. 4
What is the electron configuration of K⁺?
1s²2s²2p⁶3s²3p⁶ The element K is in the first column of the periodic table (meaning it is in the s block) and the fourth row, so its electron configuration will end with 4s¹. The electron configuration of K is 1s²2s²2p⁶3s²3p⁶4s¹. However, the K⁺ ion has one fewer electron (due to its positive charge), so the highest-energy electron must be removed from K to create K⁺, meaning its electron configuration will be 1s²2s²2p⁶3s²3p⁶.
How many protons (p) and electrons (e) are found in a Se²⁻ ion?
34 p, 36 e Se has an atomic number of 34, so it contains 34 protons. The neutral atom would have 34 electrons, but because the ion has a -2 charge, this indicates that there are two additional electrons.
How many electrons are shared between two atoms in a triple bond?
6 Two electrons are shared between two atoms in an individual bond, therefore in a triple bond 2 × 3 = 6 electrons are shared
Determine the correct formula for aluminum oxide.
Al₂O₃ Aluminum forms ions that have a +3 charge and oxygen forms ions that have -2 charge. It would take two aluminum ions to balance the charge of three oxygen ions. This is the lowest number of each ion to reach a neutral formula unit.
What is the formula for an ionic compound containing Ba²⁺ ions and Cl⁻ ions?
BaCl₂ Two ions of chlorine are needed to balance out the positive charge on the barium ion
Which has the correct name-formula combination?
Barium Oxide - BaO Consider the charge of the ions to make sure the charges are balanced. Barium forms ions with a +2 charge and oxygen forms ions with a -2 charge. The ionic formula would be BaO. Consider the charge of the ions to make sure the charges are balanced.
What is the correct formula for barium phosphate
Ba₃(PO₄)₂ Barium forms ions with a +2 charge and the phosphate polyatomic ion has a -3 charge. It would take three barium ions to balance the charge of two phosphate ions. This is the lowest number of each ion to reach a neutral formula unit.
Which atom in the C-Cl bond has a partial positive charge (δ⁺)?
C less electronegative atom has a partial positive charge Partial charges are determined by the relative electronegativities of the atoms in a bond; the less electronegative atom, which is C, has a partial positive charge.
What is the correct formula for calcium oxide?
CaO Calcium has a +2 charge and oxygen has a -2 charge.
Which has the correct name-formula combination?
Carbon tetraiodide - CI₄ Consider the prefix and the number of atoms it indicates. For example, the prefix tetra- in carbon tetraiodide indicates that there are four iodine atoms.
What is the correct formula for cobalt (lll) hydroxide?
Co(OH)₃ The (III) in cobalt(III) hydroxide indicates that the cobalt ion has a 3+ charge. Hydroxide is a polyatomic ion that has a -1 charge. Three hydroxide ions would be needed to balance the charge on the cobalt ion.
Classify the following compounds as ionic or covalent: OF₂, CuO, SeO₂.
Covalent, ionic, covalent
Determine the correct formula chromium (ll) nitrate
Cr(NO₂)₂ The (II) in chromium(II) nitrite indicates that the chromium ion has a 2+ charge. Nitrite is a polyatomic ion that has a -1 charge. Two nitrite ions would be needed to balance the charge on the chromium ion.
Which atom in the Br-F molecule has a partial negative charge (δ⁻)?
F - Florine 3.98 Consider which element in the question has the higher electronegative Partial charges are determined by the relative electronegativities of the atoms in a molecule; the more electronegative atom, which is F, has a partial negative charge.
Determine the correct formula for iron(III) perchlorate.
Fe(ClO₄)₃ The (III) in iron(III) perchlorate indicates that the iron ion has a 3+ charge. Perchlorate is a polyatomic ion with a -1 charge. Three perchlorate ions would be needed to balance the charge on iron.
Classify the following compounds as ionic or covalent: BaO, Fe₂O₃, ZnO.
Ionic, Ionic, Ionic Ionic bonds occur between a metal and a nonmetal. Covalent bonds occur between two nonmetals.
Example of a Ionic bond
K - F K-F is an ionic bond because the difference in electronegativity is greater than 1.5 and it is between a metal and a nonmetal
Which of the following is most likely to form a +2 ion?
Mg Elements in Group 2 tend to form a +2 ion by losing its two valence electrons.
What is the formula for an ionic compound containing Mg²⁺ ions and N³⁻ ions?
Mg₃N₂ Use butterfly effect Three magnesium ions are needed to balance out the negative charge on the two nitrogen ions. This is the lowest number of each ion to reach a neutral formula unit
Determine the correct formula for manganese(II) fluoride.
MnF₂ The (II) in manganese(II) fluoride indicates that the manganese ion has a 2+ charge. Fluoride has a -1 charge. Two fluoride ions would be needed to balance the charge on the manganese ion.
Write the chemical formula for the ammonium ion?
NH₄⁺
Write the chemical formula for tetraphosphorus hexasulfide
P4S6
Write the chemical formula for diphosphorus pentabromide
P₂Br₅
Which of the following represents a species with 39 protons and 36 electrons?
Y³⁺ Yttrium has an atomic number of 39 and it contains 39 protons. The neutral atom would have 39 electrons, but because there are 36 electrons, it would have +3 charge.
What is the correct IUPAC name for AlBr₃?
aluminum bromide
Correct IUPAC name for Al(NO₂)₃
aluminum nitrite
An atom has nine protons and ten electrons. This makes it:
an Ion A neutral atom has an equal number of protons and electrons. If there are more or less of one than the other, the atom is an ion.
Correct IUPAC name for BaHPO₄
barium hydrogen phosphate
What is the correct IUPAC name for BaI₂?
barium iodide
What is the correct IUPAC name for CaS?
calcium sulfide
What is the correct IUPAC name for Cs₃P?
cesium phosphide
What is the correct IUPAC name for CrCl₂?
chromium(II) chloride Cr is a transition metal therefore using roman numerals for the cation
What is the correct IUPAC name for CrBr₃?
chromium(III) bromide
What is the correct IUPAC name for Co(NO₃)₃ · 6H₂O?
cobalt (III) nitrate -hydrated ionic compound- 1. is their a transition metal -> roman numerals needed 2. list the cation element first 3. what is the second element? oxygen or no oxygen?
What is the correct IUPAC name for CuO?
copper (II) oxide with each element having 1 e and being a transition metal add them together and put it as a Romen numeral Because this compound contains a transition metal that can form cations (positive ions) with different charges, the specific charge of the cation in this compound is required in the form of Roman numerals.
What is the correct IUPAC name for Ir₂O₃?
iridium (III) oxide
What is the correct IUPAC name for Fe₃P₂?
iron (II) phosphide
What is the correct IUPAC name for FePO₄ · 4H₂O?
iron (III) phosphate tetrahydrate
IUPAC name for Li₃PO₄
lithium phosphate
IUPAC name for Mg₃(PO₄)₂?
magneisum phosphate
What is the correct IUPAC name for MgF₂?
magnesium fluoride
What is the correct IUPAC name for Mg₃P₂?
magnesium phosphide
What is the correct IUPAC name for Rb₃N?
rubidium nitride the proportion of the ions in the compound is implied by the charges of the ions
The reason an ionic bond forms is best described as
the energy change for electron transfer results in a large gain in stability when the ionic bond forms.
Correct IUPAC name for TiCl₄ ?
titanium(IV) chloride
In a covalent bond
2 atoms share valence electrons and those shared electrons form the chemical bond
Which has the correct name-formula combination?
Cobalt(III) nitrate - Co(NO₃)₂ Consider the charge of the ions to make sure the charges are balanced. For the transition metals, the charge is indicated in the name with a Roman numeral in parentheses. For example, cobalt(III) nitrate indicates that the cobalt ion has a charge of +3. Nitrate is a polyatomic ion that has a -1 charge. Three nitrate ions would be needed to balance one cobalt ion. This yields a formula of Co(NO₃)₃.
Which has the correct name-formula combination?
Iron(III) hydroxide - Fe₃OH Consider the charge of the ions to make sure the charges are balanced. For the transition metals, the charge is indicated in the name with a Roman numeral in parentheses. For example, iron(III) hydroxide indicates that the iron ion has a +3 charge. Hydroxide is a polyatomic ion that has a -1 charge. Three hydroxide ions would be needed to balance the charge on one iron ion. This yields the formula Fe(OH)₃.
Correct IUPAC name for PbF₂ ?
lead(II) fluoride
What is the correct IUPAC name for K₂O
postassium oxide
What is the formula of a compound containing K⁺ and O²⁻ ions?
K₂O Two potassium ions are needed to balance out the negative charge on the oxygen ion
Which of the following represents the electron configuration of P³⁻?
1s²2s²2p⁶3s²3p⁶ The element P is a main-group element on the right-hand side of the periodic table (meaning it is in the p block) and the third row, so its electron configuration will end with 3p. The electron configuration of P is 1s²2s²2p⁶3s²3p³. However, the P³⁻ ion has three additional electrons (due to its charge of 3-), so three electrons must be added to the atom, resulting in the electron configuration 1s²2s²2p⁶3s²3p⁶.
