Chapter 5 Quiz 1&2
When writing chemical formulas of ionic compounds, anions are written before cations. T/F
False Metal cations are written before nonmetal anions.
When writing chemical formulas the more metallic element, is normally written first. T/f
T Metals are found on the left side of the periodic table and generally appear first in the formula.
Sodium chloride is used as a flavor enhancer. T/F
T Sodium chloride is commonly called table salt.
What is the formula for the ionic compound formed from the combination of magnesium with sulfur?
MgS Magnesium always forms +2 cations and sulfur always forms −2 anions in binary compounds.
What is the name of CaCl2?
calcium chloride
A compound that consists of an alkali metal and a nonmetal is classified as what type of compound
Type I ionic Type I ionic compounds contain a metal (such as an alkali metal) that forms only one type of ion and a nonmetal.
What type of compound is KClO4?
Type I ionic Type I ionic compounds contain a metal that forms only one type of ion with one or more nonmetals (sometimes in the form of a polyatomic ion.)
Write the name of Fe3(PO4)2.
iron(II) phosphate The charge of iron must be +2 in order for the compound to be charge neutral.
N2 is what type of chemical species?
molecular element N2 is a diatomic molecule of the element nitrogen.
Na2S is a binary ionic compound of Type I.
True Sodium always forms a cation with a +1 charge.
Water has an oxygen-to-hydrogen mass ratio of 8.0:1.0. How many grams of hydrogen are in a sample of water that contains 32 g oxygen?
4.0 g A ratio of 8.0 : 1.0 is equal to a ratio of 32 : 4.0 .
16.01 g of sulfur trioxide was decomposed into 6.41 g of sulfur and 9.60 g of oxygen. How many grams of sulfur trioxide would be needed to produce 28.80 g of oxygen?
48.0 g g of sulfur trioxide = 28.80 g of oxygen x (16.01g of sulfur trioxide/9.60 g of oxygen)
The formula Al2(SO4)3 represents a compound that has what ratio of oxygen atoms to sulfur atoms?
4:1 There are three sulfur atoms and twelve oxygen atoms in one formula unit of Al2(SO4)3
What is the formula mass of CS2?
76.15 amu The formula mass of CS2 is the sum of the masses of one carbon atom and two sulfur atoms.
What number is represented by the prefix octa-?
8 Prefixes are used to indicate the subscript in the formula, here octa for 8.
Write the name of the acid H2SO4.
sulfuric acid The names of oxyacids derived from oxyanions ending in -ate are named with the suffix -ic.
Calculate the formula mass of Mg(C2H3O2) 2.
142.40 amu The formula mass is calculated by summing the atomic masses of magnesium, four carbon atoms, six hydrogen atoms, and four oxygen atoms.
Write the formula for a compound composed of calcium, carbon, and oxygen atoms in a ratio of 1:2:4.
CaC2O4 Metals are written before nonmetals. Among nonmetals the more metallic element is listed first.
The properties of a compound reflect the properties of the elements that compose it. T/F
F When elements combine to form compounds, their properties change completely.
Acids are ionic compounds T/F
F Acids are molecular compounds
N2O is a molecular compound named nitrogen dioxide. T/F
F NO2 is a molecular compound named nitrogen dioxide. N2O is named dinitrogen monoxide.
Oxyacids are composed only of a nonmetal and oxygen. T/F
F Oxyacids are composed of hydrogen, a nonmetal, and oxygen.
The basic unit of an ionic compound is a molecule. T/F
F The basic unit of an ionic compound is the formula unit.
The formula mass of carbon dioxide is 28.00 amu. T/F
F The formula mass of CO2 is 44.00 amu.
A compound is a mixture of elements. T/F
F The properties of a compound are different from the properties of the elements that produce it. Mixtures have variable composition, compounds do not.
Sodium and oxygen combine to form what type of substance?
Ionic compound Ionic compounds contain a metal and one or more nonmetals.
Write the formula for a compound composed of potassium and bromine.
KBr The charge of the K+ ion and the charge of the Br− ion cancel each other.
Write the name of CoS.
cobalt(II) sulfide CoS is a Type II compound.
Write the name of N2O5.
dinitrogen pentoxide There are two nitrogen atoms and five oxygen atoms in the molecule.
What is the name of the acid HBr?
hydrobromic acid Hydrobromic acid is a binary acid.