CHEM 104 Exam 2 Final Exam Questions and Answers Verified Solutions Latest Update 2026/2027

CHEM 104 Exam 2 Final Exam Questions
and Answers Verified Solutions Latest
Update 2026/2027
Question:
What is the number 3,000 written in scientific notation using the proper number of significant
figures?

Answer:
3 × 10^3


Question:
Which statement about the modern periodic table is FALSE?

Answer:
Elements in the same period share similar chemical and physical properties.


Question:
Which of the following is NOT a unit for measuring pressure?

Answer:
kJ


Question:
A covalent bond involves which of the following?

Answer:
sharing of electrons between two atoms


Question:

,Which statement correctly describes what is happening in the reaction shown below?
2Mg(s) + S2(g) → MgS(s)

Answer:
Mg is oxidized.


Question:
Which statement explains why isotopes have different mass numbers?

Answer:
Isotopes differ in the number of neutrons each contains


Question:
Enough water is added to 50.0 mL of a 0.660 M NaOH solution in order to bring the total volume
to 450.0 mL. What is the molarity of this diluted solution?

Answer:
0.0733 M


Question:
The unbalanced equation for the combustion of octane, a component of gasoline, is shown below.
What would be the coefficient of carbon dioxide once the equation is balanced?
C8H18(l) + O2(g) → CO2(g) + H2O(l)

Answer:
16


Question:
When a neutral atom gains one or more electrons, what type of particle is formed?

Answer:
an anion


Question:

,What is the name of the ionic compound with the formula Na3PO4?

Answer:
sodium phosphate


Question:
What law predicts the expansion of a balloon when helium is added?

Answer:
Avogadro's Law


Question:
Methanol (CH3OH) is the fuel used by racecars in the Indianapolis
500. It burns in the engine according to the equation below. How
many moles of oxygen gas are necessary to react completely with 12.5 L of methanol? [Density:
CH3OH, 0.7910g/mL; Molar mass: CH3OH, 32.05 g/mol]
2CH3OH(l) + 3O2(g) → 2CO2(g) + 4H2O(g)

Answer:
463 mol


Question:
At what temperature is a liquid converted into a gas?

Answer:
the boiling point of the liquid


Question:
The drug "lithium" is often prescribed to treat mental illness. It is not the element lithium, but the
ionic compound Li2CO3, that is actually administered. What is the name of this compound?

Answer:
lithium carbonateConsider the chemical equation shown below. How many moles of oxygen gas
are needed to react with hydrogen to form one mole of water? 2H2(g) + O2(g) → 2H2O(l)

, Question:
Hydrogen fluoride will react with glass (silicon dioxide, SiO2) according to the equation below.
What mass of HF is required to react completely with 16.0 g of glass? [Molar masses: Si, 28.09
g/mol; F, 19.00 g/mol; H, 1.01 g/mol; O, 16.00 g/mol]
4HF(g) + SiO2(s) → SiF4(g) + 2H2O(g)

Answer:
21.3 g


Question:
Two molecules of ethane experience what type of attractive forces?

Answer:
London forces


Question:
A solution contains the label 0.2 M KNO3. What is the correct interpretation of this concentration?

Answer:
There are 0.2 moles of KNO3 in 1 L of solution.


Question:
Which properly represents the Lewis structure of hydrogen sulfide, H2S?

Question:
If 5.20 g of HCl is added to enough distilled water to form 3.00 L of solution, what is the molarity
of the solution? [Molecular weight: HCl, 36.46 amu]

Answer:
0.0475 M


Question:
A patient needs 0.300 g of a solid drug preparation per day. How many 10.0 mg tablets must be
given to the patient per day?