Q: Calculate the wavelength (in meters) of light with a frequency of $$1.20 \times 10$$^{13}$$\ \mathrm{s}^{-1}. $$Use $$c = 3.00 \times 10^8$\ \mathrm{m/s}.$$

$$2.5 \times 10$$^{-5}$$\ \mathrm{m}$$

Q: Calculate the energy of a photon that has a wavelength of $$8.0\ \mathrm{m}. $$Use $$h = 6.626 \times 10$$^{-34}$$\ \mathrm{J\cdot s}$$ and $$c = 3.00 \times 10^8$\ \mathrm{m/s}.$$

$$2.48 \times 10$$^{-26}$$\ \mathrm{J}$$

Question 1

A system absorbs 220 J of heat from the surroundings and does 100 J of work on the surroundings. What is the change in internal energy $$\Delta E of $$the system?

Accepted Answer

$$\Delta E = 120 \ \mathrm{J}$$

Question 2

Which of the following is an example of an endothermic process?

Accepted Answer

Melting of ice

Question 3

For an exothermic process, what is the sign of $$\Delta H$$?

Accepted Answer

Negative

Question 4

For which of the following substances is the standard enthalpy of formation $$\Delta H_f^\circ$$ equal to zero? Select all that apply.

Accepted Answer

N$$_2 (g)$$

Question 5

Given that the standard enthalpy change $$\Delta H^\circ$$ for the reaction $$\mathrm{CH_3OH (l) \rightarrow CO (g) + 2H_2 (g)} is$$ $$+128.1\ \mathrm{kJ}$$, how much heat is consumed when $$50.0\ \mathrm{g} of CH$_3OH (l) $$decomposes as shown?

Accepted Answer

$$200.2\ \mathrm{kJ}$$

Question 6

How much heat (in J) is required to raise the temperature of $$50.0\ \mathrm{g} of $$lead from $$25^\circ \mathrm{C} to$$ $$45^\circ \mathrm{C}$$? (Specific heat of Pb = $$0.128\ \mathrm{J\ g$$^{-1}$$\ ^\circ C$$^{-1}$$})$$

Accepted Answer

$$130\ \mathrm{J}$$

Question 7

Given the following reactions:

$$2\mathrm{S} (s) + 3\mathrm{O}_2 (g) \rightarrow 2\mathrm{SO}_3 (g) \qquad \Delta H = -790\ \mathrm{kJ}$$

$$\mathrm{S} (s) + \mathrm{O}_2 (g) \rightarrow \mathrm{SO}_2 (g) \qquad \Delta H = -297\ \mathrm{kJ}$$

What is the enthalpy change for the reaction $$2\mathrm{SO}_2 (g) + \mathrm{O}_2 (g) \rightarrow 2\mathrm{SO}_3 (g)$$?

Accepted Answer

$$-196\ \mathrm{kJ}$$

Question 8

Given the following standard enthalpies of formation:

$$\mathrm{CO} (g): -110.5\ \mathrm{kJ/mol}$$
$$\mathrm{O}_2 (g): 0\ \mathrm{kJ/mol}$$
$$\mathrm{CO}_2 (g): -393.5\ \mathrm{kJ/mol}$$

Calculate $$\Delta H^\circ$$ for the reaction $$2\mathrm{CO} (g) + \mathrm{O}_2 (g) \rightarrow 2\mathrm{CO}_2 (g).$$

Accepted Answer

$$-566.0\ \mathrm{kJ}$$

Question 9

Which of the following orbitals is filled after 4s in the Aufbau principle?

Accepted Answer

3d

Question 10

What is the full and condensed electron configuration for selenium (Se, $$Z=34$$)?

Accepted Answer

$$[\mathrm{Ar}]\ 4s^2$\ 3d$$^{10}$$\ 4p^4$

Question 11

Calculate the wavelength (in meters) of light with a frequency of $$1.20 	imes 10$$^{13}$$\ \mathrm{s}^{-1}.

$$Use $$c = 3.00 	imes 10^8$\ \mathrm{m/s}.$$

Accepted Answer

$$2.5 	imes 10$$^{-5}$$\ \mathrm{m}$$

Question 12

Calculate the energy of a photon that has a wavelength of $$8.0\ \mathrm{m}.

$$Use $$h = 6.626 	imes 10$$^{-34}$$\ \mathrm{J\cdot s}$$ and $$c = 3.00 	imes 10^8$\ \mathrm{m/s}.$$

Accepted Answer

$$2.48 	imes 10$$^{-26}$$\ \mathrm{J}$$

Question 13

A spectrum containing only specific wavelengths is called a(n) ______ spectrum.

Accepted Answer

line

Question 14

How many s and p orbitals are in shell $$n=2$$? What is the total number of electrons in this shell?

Accepted Answer

One s, three p, eight electrons

Question 15

Which of the following correctly describes the trend in atomic radius in the periodic table?

Accepted Answer

Down a group and from right to left across a period

Question 16

Which of the following is an isoelectronic series?

Accepted Answer

$$\mathrm{O}^{2-},\ \mathrm{F}^-,\ \mathrm{Ne},\ \mathrm{Na}^+$$

Question 17

Which of the following correctly represents the second ionization of aluminum?

Accepted Answer

$$\mathrm{Al}^+ (g) \rightarrow \mathrm{Al}^{2+} (g) + e^-$$

Question 18

What is the electron configuration for $$\mathrm{Ti}^{2+}$$?

Accepted Answer

$$1s^2$$\ $$2s^2$$\ $$2p^6$$\ $$3s^2$$\ $$3p^6$$\ $$3d^2$$

General Chemistry: Thermochemistry, Atomic Structure, and Periodic Trends Study Guide

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