Question 1

A bakery can feed 12 people with bread in one day at a cost of $0.20. How many days would it take to feed 250 people at a party if only bread were served?

Accepted Answer

About 21 days

Question 2

Americium-243 ($$ ^{243}_{95}Am ) $$undergoes alpha decay. What is the nuclear symbol of the resulting daughter nucleus?

Accepted Answer

$$ ^{239}_{93}Np $$

Question 3

Which of the following correctly represents an alpha particle, including its charge?

Accepted Answer

$$ ^{4}_{2}He$$^{2+}$$ $$

Question 4

In the Millikan oil drop experiment, if you wanted to measure the charge of a positron instead of an electron, what modification would you need to make?

Accepted Answer

Reverse the direction of the electric field

Question 5

Given the following droplet charges measured in a modified Millikan experiment for positrons: $$+4.8066 	imes 10$$^{-19}$$ C, +9.6125$$ 	imes $$10^{-19} C$$, $$+11.2154 	imes 10$$^{-19}$$ C, +17.6224$$ 	imes $$10^{-19} C$$, $$+20.8286 	imes 10$$^{-19}$$ C, what is the charge of a single positron to 4 decimal places?

Accepted Answer

$$1.6022 	imes 10$$^{-19}$$ C

Question 6

An element X has two isotopes: one with a mass of 36.8462 amu and the other with a mass of 39.1283 amu. If the average atomic mass is 37.1234 amu, what is the percent abundance of the lighter isotope? (Report to two decimal places.)

Accepted Answer

89.13%

Question 7

What is the minimum energy, in joules, required to ionize a hydrogen atom from its ground state?

Accepted Answer

$$2.18 	imes 10$$^{-18}$$ J

Question 8

If an ejected electron from platinum has a velocity of $$4.382 	imes 10$$^{6}$$ m/s, what is its kinetic energy in joules? (Use m_e = 9.11$$ 	imes $$10^{-31} kg)$$

Accepted Answer

$$8.74 	imes 10$$^{-18}$$ J

Question 9

What is the longest wavelength of light, in nm, that can eject an electron from the surface of platinum if the work function is $$6.35 	imes 10$$^{-19}$$ J? (Use c = 3.00$$ 	imes $$10^{8} m/s$$, $$h = 6.626 	imes 10$$^{-34}$$ J·s)

Accepted Answer

313 nm

Question 10

Which of the following quantum number sets is valid for an electron in a 3p orbital?

Accepted Answer

$$n=3,\ l=1,\ m_l=0,\ m_s=+\frac{1}{2}$$

Question 11

For a tellurium (Te) atom, which electron is easiest to remove/ionize?

Accepted Answer

The electron with the highest principal quantum number $$n$$ and highest $$l$$

Question 12

Which species below has the most negative electron affinity?

Accepted Answer

$$Cl^{-}$$

Question 13

Which of the following species is the largest in size?

Accepted Answer

$$P$$

Question 14

Which of the following species has the lowest ionization energy?

Accepted Answer

$$Na^{0}$$

Question 15

The biggest difference between successive ionization energies for magnesium will be between the ______ and ______ ionizations.

Accepted Answer

2nd and 3rd

Question 16

Which equation correctly relates the energy of a photon to its frequency?

Accepted Answer

$$E = h 
u$$

Question 17

Which of the following best explains why the work function is important in the photoelectric effect?

Accepted Answer

It is the minimum energy required to remove an electron from the surface of a metal

Question 18

Which of the following is the correct value for Avogadro's number?

Accepted Answer

$$6.022 	imes 10$$^{23}$$

General Chemistry I: Atomic Structure, Radioactivity, and Quantum Concepts – Exam Study Guide

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