Final Exam Review #1

Atomic Symbols

100

What element has 20 protons and a mass of 40 g/mol? 

Calcium 

200

How many protons, electrons, and neutrons does the element Sulfur have?

P⁺: 16

E^-: 16

N: 16

300

What element has the atomic symbol of Se? How many protons, electrons, and neutrons does it have?

Selenium

P⁺: 34

E^-: 34

N: 44

400

What element has the atomic symbol of Mn? How many protons, electrons, and neutrons does Mn have?

Manganese

P⁺: 25

E^-: 25

N: 29

500

What element is Xe? How many neutrons does a neutral Xe have? How many moles are 100.g of Xe?

Xenon

77 neutrons

0.762 moles

Moles/Molar Mass

100

What is Avogadro's number and what does it count?

6.022 x 10²³

Things, usually molecules or atoms

200

How many moles are in 85.47g of Rubidium?

1 mol

300

How many grams of Copper are in 0.47 moles of copper? 

30 grams of copper 

400

Tin's molar mass is 118.71 g/mol. How many moles are in 182.g of tin?

1.53 moles 

500

Krypton is a noble gas. What is its molar mass? How many grams are in 2.12 moles of krypton?

Molar Mass = 83.80 g/mol

178 g of krypton

Electron Configurations/Paired Electrons

100

What is the electron configuration for Magnesium?

[Ne]3s²

200

What is the electron configuration for chromium? How many unpaired electrons does it have? 

[Ar]4s²3d⁴

4 unpaired electrons

300

What is the electron configuration of Br? How many unpaired electrons does it have?

[Ar]4s²3d¹⁰4p⁵

1 unpaired electron

400

What is the extended electron configuration of silver?

1s²2s²2p⁶3s²3p⁶4s²3d¹⁰4p⁶5s²3d⁹

500

What is the extended electron configuration of sulfur? How many unpaired electrons does it have?

1s²2s²2p⁶3s²3p⁴

2 unpaired electrons

Lewis Structures

100

How many valence electrons does calcium have?

2 valence electrons

200

How many valence electrons does chlorine have? Name 3 elements/ions that are isoelectronic with Cl^-.  

7 valence electrons

Si^4-, P^3-, S^2-,Ar, K⁺, Ca²⁺, Sc³⁺, Ti⁴⁺

300

How can we make ionic bonds stronger?

1. Decrease distance between ions

2. Increase the charges

400

What is the electron and molecular geometry of NH₃? What is its ideal bond angle? Is it polar?

Tetrahedral, trigonal pyramidal

<109.5^o

Yes, it is polar

500

What are the electron and molecular geometry of CH₂O? What is the ideal bond angle? Is it polar?

Trigonal planar, trigonal planar

120^o 

Yes, it is polar

Miscellaneous

100

What is density and what are its units?

D= m/v = g/mL

200

What is a buffer and what does it resist?

A buffer is a weak acid-conjugate pair that resists changes in pH when H⁺, OH^-, and water are added. 

300

What are the types of nuclear radiation that we learned?

Alpha particle

Beta particle

Gamma particle

Positron

400

In general, what are the relative melting points and boiling points of ionic compounds compared to covalent compounds?

Ionic compounds' melting and boiling points are much higher than covalent compounds'. 

500

How does soap work?

Soap's polar 'head' is attracted to dirt(non polar) while soap's non polar 'tail' is attracted to water(polar). The soap then washes the dirt and water down the drain.