Chemistry Semester 1 Final
The average mass of a boron atom is 10.81. Assuming you were able to isolate only one boron atom, the chance that you would randomly get one with a mass of 10.81 is
0%
Which represents the greatest mass?
1.0 mol Zn
A mole of sulfur trioxide molecules contains how many oxygen atoms?
1.807 x 10^24
How many protons are in the nucleus of a Mg atom?
12
The number 14.809 rounded to three significant figures is
14.8
If a 100. g sample of a metal has a volume of 5.18 mL, what is the density of the metal?
19.3 g/mL
The electron configuration for the phosphorus atom is
1s^2 2s^2 2p^6 3s^2 3p^3
How many of the following are compounds: table salt, carbon, copper, water, mercury?
2
In the product 1.04 x 0.31, the number of significant figures is
2
The maximum number of electrons allowed in each of the p orbitals is
2
The number 200,000 expressed in scientific notation is
2 x 10^5
How many milliliters are in 0.020 L?
20.0 mL
What is the Celsius equivalent of 481 K?
208°C
Perform the following conversion: 6.00 m/s = _____ km/hr
21.6
How many atoms are represented by one formula unit of aluminum dichromate, Al2(Cr2O7)3?
29
How many atoms of hydrogen are in one molecule of CH3Cl?
3
How many significant figures are in the number 0.0908?
3
A 20.0 g sample of Ca contains how many calcium atoms?
3.0 x10^23 atoms
When the equation Si(s) + HF(aq) --> SiF4(g) + H2(g) is balanced, what is the coefficient for HF?
4
The number 0.000402 expressed in exponential notation is
4.02 x 10^-4
The number of cubic centimeters (cm3) in 43.0 mL is
43.0 cm^3
When the following equations are balanced using the smallest possible integers, what is the number in front of the underlined substance in each case? PCl5 + H2O --> H3PO4 + HCl
5
How many electrons are present in a tin atom with a mass number of 119?
50
The molar mass of magnesium hydroxide is
58.3 g/mol
One mole of something consists of _____ units of that substance.
6.022 x 10^23
How many significant figures are in the number 6.987010?
7
What is the molar mass of Al(OH)3?
78.00 g/mol
The density of copper is 8.92 g/mL. The mass of a piece of copper that has a volume of 10.0 mL is
89.2 g
How many electrons are present in a fluorine, F, atom?
9
Which of the following contains the largest number of oxygen atoms?
Al(NO3)3
An example of a pure substance is
All of the above
Which of the following elements is most similar to chlorine?
Br
Choose the pair of compounds with the same empirical formula.
C2H2 and C6H6
The empirical formula for acetic acid is CH2O. Its molar mass is 60 g/mol. The molecular formula is
C2H4O2
A gaseous compound containing carbon and hydrogen was analyzed and found to consist of 83.65% carbon by mass. What is the empirical formula of the compound?
C3H7
Which of the following has the largest percent (by mass) of carbon?
CH4
The correct formula for the carbonate ion is
CO32-
Which of the following formulas is incorrect?
CsCl2
Order the elements S, Cl, and F in terms of increasing atomic radii.
F, Cl, S
Which, if any, of the following is named incorrectly?
Fe(OH)2; iron(III) hydroxide
The correct formula for iron(III) phosphide is
FeP
Which of the following is named correctly?
HNO3(aq); nitric acid
Of the metals in Group 1, which has the highest ionization energy?
Li
An atom with 15 protons and 16 neutrons is an atom of
P
The correct formula for lead(IV) nitrate is
Pb(NO3)4
What is the formula for sulfur hexafluoride?
SF6
Titanium(IV) oxide has the formula
TiO2
A substance composed of two or more elements combined chemically in a fixed proportion by mass is
a compound
The fundamental particle of a chemical element according to Dalton's theory is the
atom
Which of the following is a nonmetal?
carbon
Which atomic particle determines the chemical behavior of an atom?
electron
Which particle has the smallest mass?
electron
The fundamental unit of mass in the metric system is the
gram
The lowest possible energy state of an atom is called its _____ state.
ground
The correct name for an aqueous solution of HCl is
hydrochloric acid
Which of the following is an element?
iron
The correct name for FeO is
iron(II) oxide
What is a summary of observed behavior?
law
The name of the compound Pb(NO3)2 is
lead(ll) nitrate
The name for the NO3- ion is
nitrate ion
Choose the correct name for HNO2.
nitrous acid
Which of the following is an element?
oxygen
The compound PI3 is named
phosphorus triiodide
When moving down a group (family) in the periodic table, the number of valence electrons
remains constant
Which of the following is a chemical change?
silverware tarnishes
The mass number of an atom equals
the number of protons plus the number of neutrons per atom
All of the following are clues that a chemical reaction has taken place except
the reactant is smaller
