Ionic/Molecular Relationships
What is the ionic compound that forms calcium and oxygen?
A) CaO
B) Ca2O
C) CaO4
D) Ca3O2
E) Ca2O3
A) CaO
Consider the math problem below:
125.79 - (15.5 + 2.079) = ?
125.79−17.6=108.19
≈108.2 (1 decimal place)
Which measurement represents the longest distance?
A) 5.2 x 10-4m
B) 5200 µm
C) 5.2 cm
D) 5.2 x 10-6 km
E) 0.52 mm
C) 5.2 cm = 0.052 m.
Ammonium nitrate, NH4NO3, is a common fertilizer. How many grams of ammonium nitrate are in 8.00 x 10^-2 moles of NH4NO3?
8.00×10^-2moles × 80.05g/mol=6.404g
= 6.40g NH4NO3
Determine if polar or not NF3
polar, lone pair on nitrogen
What is the formula of ammonium and sulfur?
(NH4)2S
Which of the following corrrectly lists the elements in order of increasing ionization energy?
*smallest ionization energy to largest ionization energy (left to right)
A) Rb < Na < F < S
B) F < Na < S < Rb
C) Rb < Na < S < F
D) F < S < Na < Rb
E) Na < Rb < S < F
C) Rb < Na < S < F
One pound (lb) contains 454 grams. what is the following calculation setup (conversion) that would convert micrograms to pounds (lb)?
µg × (1g/1,000,000μg) × (1lb/454g)
Air bags in vehicles inflate when the following reaction occurs:
2NaN3(s) --> 2Na(s) + 3N2(g)
How many moles of NaN3 are required to produce 0.535 moles of N2 gas?
0.535 mol N2 x 2mole NaN3 / 3mole N2
= 0.357 moles of NaN3
Strongest intermolecular force KCl?
ionic forces
NaClO is in household bleach. What is the name of this ionic compound?
A) sodium chlorite
B) sodium chloride
C) sodium chlorate
D) sodium perchlorate
E) sodium hypochlorite
E) sodium hypochlorite
Identify which is reduced or oxidized
2PbO --> 2Pb + O2
The O is oxidized and Pb is reduced
The density of gasoline is 0.74 g/mL. What is the mass in grams of gasoline that fills a 12 L container?
12L x 1000mL/1L x 0.74g/1mL = 8880 g
= 8900 g
Which sample has the largest mass in grams?
A) 1 mole N2
B) 1 mol O2
C) 1 mol HF
D) 1 mol H20
E) 1 mol CO
B) 1 mol O2 = 32.00g/mol
Determine which has higher melting point:
HF and HBr
HF because hydrogen forces are stronger than HBr dipole dipole forces
Which of the following compound names is correctly stated for the formula given?
A) manganese(III) oxide; MnO
B) iron(II) oxide; FeO
C) phosphorus(III) sulfide; PS3
D) nitride trichloride; NCl3
E) carbon fluoride; C6F6
B) iron(II) oxide; FeO
What is the balanced chemical equation for the decomposition of solid aluminum oxide to form solid aluminum and molecular oxygen gas?
A) 2AlO3 (s) --> 2Al (s) + 3O2 (g)
B) 2Al2O3 (s) --> 4Al (s) + 3O2 (g)
C) Al3O2 (s) --> 3Al (s) + O2 (g)
D) 2Al (s) + 3O2 (g) --> 2AlO3 (s)
E) 2AlO(s) --> 2Al(s) + O2 (g)
B) 2Al2O3 (s) --> 4Al (s) + 3O2 (g)
A carpet has an area of 1.6 x 10^5 cm^2. What is the area of the carpet in square meters?
1.6x10^5 cm^2 x (1/10,000cm)^2
= 16 m^2
Consider the following reaction:
2K(s) + 2H2O(l) --> 2KOH(aq) + H2(g)
What is the conversion factor that would be best used in the calculation to determine the number of moles of hydrogen gas formed when 7.54 moles of H2O completely react?
=7.54 mol H2O x 1mole H2 / 2mole H2O
How many lone pairs (nonbonding pairs) of electrons are on the central atom in the molecule SeCl2? Note: Se is the central atom.
N: 24e-
A: 20e-
S: 4e- = 2 bonds
L: 16e-
= 2 lone pairs
Which of the following pairs of atoms or ions have the exact same number of total electrons?
A) Ca2+ and Ar
B) Li+ and Li
C) K+ and Br-
D) Al3+ and B3+
E) Ne and F
A) Ca2+ and Ar = both with 18 electrons
When the following unbalanced chemical equation is balanced,
__ Cr (s) + __ O2 (g) --> __ Cr2O3 (s)
_4_ Cr (s) + _3_ O2 (g)--> _2_ Cr2O3(s)
A doctor orders a patient to receive 15 grams of glucose through an intravenous (IV) infusion. A nurse retrieves an IV solution with 50.0 grams of glucose per 1000. mL of solution and set the IV pump to deliver the solution at a rate of 0.70mL/min. How many hours are needed to deliver the 15 grams of glucose?
15g x 1000mL/50grams x 1 min/0.70mL x 1hour/60 minutes = 7.14
= 7.1 h
How many iron (Fe) atoms are in a sample of Fe2O3 containing 0.32 mol of Fe2O3?
0.32mol Fe2O3 x 6.022x10^23/1mole x 2 mole Fe/1 atom =
3.9 x 10^23 iron atoms
Indicate the positive and negative side of the dipole and draw the arrow:
P and Br
P+-Br- (arrow towards the br)