Honors Chemistry Chapter 10 Assessment
What is the percent composition of the compound formed when 2.70 g of aluminum combine with oxygen to form 5.10 g of aluminum oxide
% Al=mass Almass/compound x 100%= 2.70g/5.10g x 100%=53% % O=mass O/mass compound x 100%= 2.40g/5.10g x 100%=47%
Calculate the percent composition when 13.3 g Fe combine completely with 5.7 g O
% Fe=mass Fe/massFe2O3/ x 100%=111.6g/159.6g x 100%=70.0% % O=mass O/massFe2O3 x 100%=48.0g/159.6g x 100%=30%
How many moles is 5.96g KOH
0.106 KOH
How many moles is 15.5g SiO2
0.258 mol SiO2
Calculate the number of moles in 1.00 x 10^2 g of sucrose (C12H22O11)
0.292 mol
Calculate the number of moles in 1.00 x 10^2 g of potassium permanganate (KMnO4)
0.633 mol
Find the mass of 0.780 mol Ca(CN)2
0.780 x 92 = 71.8 g
Which of the following contains the largest number of atoms: 82.0 g Kr; 0.842 mol C2H4; or 36.0 g N2
0.842 mol C2H4
Which contains more atoms: 1.00 mol H2O2, 1.00 mol C2H6 or 1.00 mol CO
1.00 mol C2H6
How many moles is 79.3g Cl2
1.12 mol Cl2
How many atoms of C are in 2.00 mol of sucrose (chemical formula is C12H22O11)
1.44 x 10^25 C atoms
Find the mass of 1.50 mol C5H12
1.50 mol C5H12 = 1.50 x 72 = 108.00 g
Calculate the volume of 7.64 mol Ar at STP
1.71 L Ar
Calculate the number of moles in 1.00 x 10^2 g of sodium chloride (NaCl)
1.71 mol
Find the number of representative particles in 3.00 mol Sn
1.81 x 10^24 atoms Sn
How many hydrogen atoms are in a representative particle of C4H100
10
Calculate the molar mass of CaCO3
100.1 g/mol
Calculate the mass of 1.00 mol of iron (III) hydroxide (Fe(OH)3)
106.8 g/mol
Calculate the molar mass of (NH4)2SO4
132.1 g/mol
Find the mass of 14.4 mol F2
14.4 x 38 = 547.2 g
Calculate the mass in grams of 0.250 mol of sodium chloride (NaCl)
14.6 g
Find the number of moles in 9.03 x 10^24 atoms of Hg
15.0 mol Hg
What is the density of O2 at STP
15.999 x 2 = 32g 32g / 22.4L = 1.43 g/L
Calculate the number of grams of phosphorus in 804g Na3PO4 (using the percent composition information of 42.1% Na; 18.9% P; 39.0% O)
152g P
Calculate the molar mass of Br2
159.8 g/mol
Calculate the grams of oxygen in 90.0g of Cl2O
16.6g O
How many hydrogen atoms are in a representative particle of H2C2O4
2
How many mole is 0.800g Ca
2.00 x 10^-2 mol Ca
Find the number of representative particles in 0.400 mol KCl
2.41 x 10^23 formula units Kcl
How many atoms of O are in 3.65 mol of sucrose (chemical formula is C12H22O11)
2.42 X 10^25 O atoms
How many atoms of H are in 2.00 mol of sucrose (chemical formula is C12H22O11)
2.65 x 10^25 H atoms
How many atoms are in 1.00 mol of sucrose (chemical formula is C12H22O11)
2.71 x 10^25 atoms
The molecular formula of an antibacterial drug is C17H18FN3O3. How many fluorine atoms are in a 150-mg tablet of this drug?
2.73 x 10^20 F atoms
Find the number of representative particles in 4.80 x 10^-3 mol NaI
2.89 x 10^21 formula units NaI
Find the mass, in grams, of a molecule of aspirin (C9H8O4)
2.99 x 10^-22 g C9H8O4
What is the density of Ne at STP
20.18g / 22.4 L = 0.900 g/L
A gas has a density of 0.902 g/L at STP. What is the molar mass of this gas
20.2 g/mol
What is the volume of one mole of any gas at STP
22.4 L
Calculate the percent composition of (NH4)2C2O4
22.6% N 6.5% H 19.4% C 51.6% O
What is the total mass of a mixture of 3.50 x 10^22 formula units Na2SO4, 0.500 mol H2O, and 7.23G AgCl
24.5 g
Calculate the mass of 1.00 mol of diatomic nitrogen (N2)
28.0 g/mol
How many hydrogen atoms are in a representative particle of Al(OH)3
3
Find the number of atoms in 5.78 mol NH4NO3
3.13 x 10^25 atoms
Find the mass of 3.21 x 10^-2 mol Ni
3.21 x 10^-2 x 59 = 1.89 g
Calculate the number of grams of sulfur in 3.54g H2S (using the percent composition information of 5.96% H and 94.1% S)
3.33 g S
Calculate the volume of 1.34 mole SO2 at STP
30.0 L SO2
Calculate the mass in grams of 0.250 mol of potassium permanganate (KMnO4)
39.5 g
Find the number of moles in 2.41 x 10^24 formula units of NaCl
4.00 mol NaCl
Find the number of representative particles in 7.50 mol SO2
4.52 x 10^24 molecules SO2
How many moles is 0.0688g AgCl
4.80 x 10^-4 mol AgCl
Calculate the number of grams of magnesium in 97.4g Mg(OH)2 (using the percent composition information of 41.7% Mg; 54.9% O; 3.4% H)
40.6g Mg
Calculate the percent composition of Mg(OH)2
41.7% Mg 54.9% O 3.4% H
Calculate the percent composition of Na3PO4
42.1% Na 18.9% P 39.0% O
Calculate the volume of 2.45 x 10^-3 mol H2S at STP
5.49 x 10^-2 L H2S
Find the mass of 5.60 mol NaOH
5.60 x 40 = 224.00 g
Calculate the number of grams of nitrogen in 25.0g (NH4)2C2O4 (using the percent composition information of 22.6% N; 6.5% H; 19.4% C; 51.6% O)
5.65 g N
Calculate the percent composition of H2S
5.9% H 94.1% S
How many moles is 937g Ca(C2H3O2)2
5.93 mol Ca(C2H3O2)2
Calculate the mass of 1.00 mol of silicon dioxide (SiO2)
60.1 g/mol
Calculate the mass of 1.00 mol of copper (Cu)
63.5 g/mol
Find the mass of 7.00 mol H2O2
7.00 x 34 = 238.00 g
Find the number of moles in 4.65 x 10^24 molecules of NO2
7.72 mol NO2
What is the molar mass of chlorine
71.0 g/mol Cl2
Calculate the molar mass of N2O3
76.0 g.mol
Find the volume, in liters, of 835 g SO3 at STP
835gSO3(1mol/ 80.07g)=10.4 (22.4l / 1mol) = 233.5956 L = 234 L
Calculate the mass in grams of 0.250 mol of sucrose (C12H22O11)
85.5 g
Calculate the molar mass of C4H9O2
89.0 g/mol
How many hydrogen atoms are in a representative particle of (NH4)2HPO4
9
Calculate the volume of 0.442 mol C2H6 at STP
9.90 L C2H6
Calculate the molar mass of H3PO4
98.0 g/mol
What is wrong with the statement: One molar mass of CO2 contains Avogadro's number of atoms
A mole of CO2 has 3 times Avogadro's number of atoms
Describe the relationship between Avogadro's number and one mole of any substance.
A mole of any substance always contains Avogardo's number of representative particles, or 6.02 x 10^23 particles.
What is wrong with the statement: One mole of any substance contains the same number of atoms
A molecule is composed of two or more atoms
What is the density of C3H8 at STP
C = 12.011 x 3 = 36.04 H = 1.008 x 8 = 8.07 36.04 + 8.07 = 44.11 44.11g / 22.4 L = 1.96 g/L
What is the empirical formula of a compound with 32.00% C, 42.66% O, 18.67% N and 6.67% H
C2O2NH5
What is the molecular formula for CH2O, 90 g/mol (empirical formula and molar mass are given)
C3H6O3
What is the empirical formula of a compound with 71.72% CL, 16.16% O and 12.12% C
CL2OC
What is the empirical formula of a compound with 42.9% C and 57.1% O
CO
List three common ways that matter is measured. Give examples of each
Count; example is counting sheep Volume; example is estimating the number of jelly beans in a jar Mass; an example is weighing out some NaCl
List the steps you would take to calculate the molar mass of any compound
Determine the moles of each atom from the formula Look up the atomic mass of each element Multiply the number of moles of each atom by its molar mass Sum these products
What is the molecular formula for a compound with 94.1% O and 5.9% H; molar mass = 34 g/mol
H2O2
What is an empirical formula
Has the lowest whole-number ratio of elements
What is the molecular formula for HgCl, 472.2 g/mol(empirical formula and molar mass are given)
Hg2Cl2
What is the density of NO2 at STP
N = 14.007 O = 15.999 x 2 = 32.00 14.007 + 32.00 = 46.007 46.007g / 22.4 L = 2.05 g/L
Can C6H10O4 be classified as an empirical formula?
NO because you can reduce this ratio to C3H5O2. Therefore it is not the smallest whole number ratio.
Can S2CL2 be classified as an empirical formula?
NO because you can reduce this ratio to S1Cl1. Therefore it is not the smallest whole number ratio.
Do NaCrO4 and Na2CR2O7 have the same empirical formula?
No.
What is wrong with the statement: A mole and a molecule of a substance are identical in amount
There are 6.02 x 10^23 molecules in 1 mol of a molecular substance.
Which contains more molecules: 1.00 mol H2O2, 1.00 mol C2H6 or 1.00 mol CO
They all contain 6.02 x 10^23 molecules
Can Na2SO3 be classified as an empirical formula?
YES because you cannot reduce down any further.
Is DEET (C12H17ON) both a molecular formula and an empirical formula
Yes both molecular and empirical
Is chlorophyll (C55H72MgN4O5) both a molecular formula and an empirical formula
Yes both molecular and empirical
Do C2H4O2 and C6H12O6 have the same empirical formula?
Yes. Empirical formula is the minimal multiplication of each atom in the molecule... so they both have the empirical formula of CH2O.
How can you determine the molar mass of a gaseous compound if you do not know its molecular formula?
You can measure the mass of 22.4 L of the compound at STP; this is the molar volume of the gas. The mass of the molar volume is the molar mass.
Name the representative particle (atom, molecule, or formula unit for potassium
atom
Name the representative particle (atom, molecule, or formula unit for sodium sulfide
formula unit
Name the representative particle (atom, molecule, or formula unit for oxygen gas
molecule
Name the representative particle (atom, molecule, or formula unit for sulfur dioxide
molecule
Is ethyl butyrate (C6H12O2) both a molecular formula and an empirical formula
no just molecular
Is ribose (C5H10O5) both a molecular formula and an empirical formula
no just molecular
