Q: Due to increased concentrations of greenhouse gases, the average temperature of Earth is rising. If the heat capacity of seawater is $$4.18\ \mathrm{J/(g\cdot K)}$$ and the mass of the ocean is $$1.35 \times 10$$^{21}$$\ \mathrm{kg}$$, how much energy is required to raise the temperature of the ocean by $$1.0\ ^\circ\mathrm{C}$$?

$$5.64 \times 10$$^{24}$$\ \mathrm{J}$$

Q: Neutron stars are believed to be composed of solid nuclear matter. If the radius of a neutron is $$1.0 \times 10$$^{-13}$$\ \mathrm{cm}$$, calculate its density in $$\mathrm{g/cm^3$}$$, assuming its mass is $$1.67 \times 10$$^{-24}$$\ \mathrm{g}.$$

$$4.0 \times 10$$^{14}$$\ \mathrm{g/cm^3$}$$

Question 1

In 2020, Moderna developed an mRNA-based vaccine against COVID-19. If each dose contains 0.09 mg/mL of mRNA and the required dose is 100 μg, what volume of the vaccine suspension should be injected to deliver the required dose of mRNA?

Accepted Answer

$$1.11\ \mathrm{mL}$$

Question 2

A NASA satellite discovered in 2021 a new ozone hole over Antarctica. If the hole has a surface area of $$23.5\ \mathrm{million\ km^2$}$$ and a diameter of $$5.6\ \mathrm{km}$$, what is the approximate circumference of the ozone hole?

Accepted Answer

$$17.6\ \mathrm{km}$$

Question 3

Titanium is commonly used in medical implants. If you have $$0.250\ \mathrm{mol} of $$titanium, what is the mass in grams? $$(	ext{Atomic mass of Ti} = 47.87\ \mathrm{g/mol})$$

Accepted Answer

$$11.97\ \mathrm{g}$$

Question 4

Due to increased concentrations of greenhouse gases, the average temperature of Earth is rising. If the heat capacity of seawater is $$4.18\ \mathrm{J/(g\cdot K)}$$ and the mass of the ocean is $$1.35 	imes 10$$^{21}$$\ \mathrm{kg}$$, how much energy is required to raise the temperature of the ocean by $$1.0\ ^\circ\mathrm{C}$$?

Accepted Answer

$$5.64 	imes 10$$^{24}$$\ \mathrm{J}$$

Question 5

Given the isotopic masses and abundances for Ne: $$^{20}\mathrm{Ne} (19.992 $$amu, 90.5%), $$^{21}\mathrm{Ne} (20.994 $$amu, 0.3%), $$^{22}\mathrm{Ne} (21.991 $$amu, 9.2%), what is the average atomic mass of neon?

Accepted Answer

$$20.18\ \mathrm{amu}$$

Question 6

Neutron stars are believed to be composed of solid nuclear matter. If the radius of a neutron is $$1.0 	imes 10$$^{-13}$$\ \mathrm{cm}$$, calculate its density in $$\mathrm{g/cm^3$}$$, assuming its mass is $$1.67 	imes 10$$^{-24}$$\ \mathrm{g}.$$

Accepted Answer

$$4.0 	imes 10$$^{14}$$\ \mathrm{g/cm^3$}$$

Question 7

Hemoglobin is a protein that carries oxygen in the blood. If the formula for hemoglobin is $$\mathrm{C$$_{2952}$$H_{4664}O$$_{832}$$N_{812}S_8Fe$$}$$, how many moles of iron are present in 1.0$$\ \mathrm{mol}$ of hemoglobin?

Accepted Answer

$$1.0\ \mathrm{mol}$$

Question 8

Which of the following is the correct name for $$\mathrm{K_2O}$$?

Accepted Answer

Potassium oxide

Question 9

Which of the following compounds contains both ionic and covalent bonds?

Accepted Answer

$$\mathrm{Na_2CO_3}$$

Question 10

A sample of gas at $$25^\circ\mathrm{C}$$ and $$1.00\ \mathrm{atm}$$ occupies $$2.50\ \mathrm{L}. $$What volume will it occupy at $$50^\circ\mathrm{C}$$ and $$1.00\ \mathrm{atm}$$? (Assume ideal gas behavior.)

Accepted Answer

$$2.72\ \mathrm{L}$$

Question 11

Which of the following best explains why water has a high boiling point compared to other group 16 hydrides?

Accepted Answer

Hydrogen bonding between water molecules

Question 12

Which of the following is the correct formula for lead(II) carbonate?

Accepted Answer

$$\mathrm{$$PbCO_3$$}$$

Question 13

Which of the following is the correct name for $$\mathrm{$$NaBrO_3$$}$$?

Accepted Answer

Sodium bromate

Question 14

Which of the following best describes the process of calculating the molar mass of a compound?

Accepted Answer

Sum the atomic masses of all atoms in the formula

Cumulative Chemistry Final Exam Review: Key Concepts and Problem-Solving Strategies

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