CHM 110 Review

Exam 1 (conversions, sig figs, isotopes, molecular/empirical)

100

.057 x (17.00009 + 32052.10)= 

What is 1800? (2 sig figs)

200

Write isotopic symbols in the form for each isotope (mass on top, # on bottom)

1. The copper isotope with 34 neutrons

2. The potassium isotope with 21 neutrons 

3. The argon isotope with 22 neutrons 

1. Cu⁶³₂₉

2. K⁴⁰₁₉

3. Ar₁₈⁴⁰

300

Convert 85.6 ft³ into mL with correct number of sig figs

85.6ft³ x (12in/1ft)³ x (2.54cm/1in)³ x (1mL/1cm³) = 2423922.1 = 2420000 = 

What is 2.42 x 10⁶?

400

1. Bromine has two naturally occurring isotopes (Br-79 and Br-81) and has an atomic mass of 79.904 amu. The mass of Br-81 is 80.9163 amu, and its natural abundance is 49.31%. Calculate the mass and natural abundance of Br-79. Answer in 4 sig figs.

What are 50.69% and 78.92 amu?

500

Combust 0.1156g of compound containing only C,H,N. You capture 0.1638g CO2 and 0.1676g H2O. What is the empirical formula of the compound?

What is CH5N?

Exam 2 (Nomenclature, balancing equations, LRs, yields)

100

Name each compound  

1. S₅Br

2. HC₂H₃O₂

3. (NH₄)₃PO₄

4. Be(OH)₂

5. HF

1. Pentasulfur Monobromide

2. Acetic acid 

3. Ammonium Phosphate 

4. Beryllium Hydroxide 

5. Hydrofluoric acid

200

Balance the following equation:  

___C7H6O2 + ___O2 → ___CO2 + ___H2O

2, 15, 14, 6

300

Write the NET ionic equation for: 

Hydrochloric acid reacts with ammonia.

What is 

H+(aq) + NH3(aq) → NH4⁺(aq)?

400

What is the percent yield if 0.819g of potassium reacts with oxygen to produce 0.785g of potassium oxide?

What is 79.56%?

500

Find the limiting reactant for each initial amount of reactants using the following equation:

Al(s) + O2(g) -> Al2O3(s)

1. 1mol Al, 1mol O2

2. 4mol Al, 2.6mol O2

1. Al

2.O2

Exam 3 (gas laws and thermo)

100

7. In a mixture of the two gases, the partial pressures of CH4 and O2 are 0.175atm and 0.250 atm, respectively. What is the  mole fraction for each of the gases?

CH4= 0.412 

O2= 0.588

200

What is the pressure of oxygen gas that contains 1.73 moles in a 36L container. The container is at a temperature of 20℃.

What is 1.2atm?

300

What mass of C₂H₆ (30.07g/mol) must be combusted to produce 982kJ of heat?

C₂H₆ (g) + O₂(g) ->CO₂(g) + H₂O(l)      ΔH=-3119kJ

What is 18.93g C₂H₆ ?

400

A 7.9g sample of solid NaOH (39.97g/mol) is dissolved in enough water in a coffee cup calorimeter to make 175mL of solution. If the temperature increases from 23C to 35C, what is the change of H for in kJ/mol of NaOH? Assume density is 1g/mL and heat capacity is 4.18J/g*C.

-44kJ/mol 

500

Which of the following systems would undergo the greatest temperature change upon absorbing 100J of heat?

1. 10g lead (0.128J/g℃)

2. 10g ethanol (2.42J/g℃)

3. 10g copper (0.385J/g℃)

4. 12g aluminum (0.903J/g℃)

5. 12g water (4.18J/g℃)

What is 1) 10g lead (0.128J/g℃) ?

Exam 4 (quantum mechanics, geometry, lewis dot)

100

1. An element that has the valence electron configuration ns2np5 belongs to which group? 

2. Which one of the following ions is isoelectronic with a noble gas?  

(a) Sc2+         (b) Y2+        (c) Fe3+        (d) Br-         (e) Sn2+ 

3. Write the shorthand electron configuration AND the orbital diagram for Mn2+ 

1. What is halogen group?

2. What is d?

3. [Ar]3d5

200

Name the geometry and if it is polar or nonpolar:

1. F2

2. CH2O

3. NH3

1. linear, nonpolar

2. polar, trigonal planar

3. polar, trigonal pyramidal

300

Draw best lewis structure for [NO2]-1 and explain why.

O-N=O

because formal charges are -1, 0, 0

and O is most electronegative with most negative charge.

400

Rank the ionic compounds to greatest lattice energy: K2O FeO and FrI

FrI< K2O< FeO

500

Using the bond enthalpies provided, calculate ΔH for the following reaction. CH3CH3 + Br2 → CH3CH2Br + HBr

What is -33kJ?

Chapter 12 & 14 (IMF, phase changes)

100

Label IMFs from weakest to stronges (include ion-dipole)

london --> dipole-dipole --> Hbonding --> ion-dipole

200

Find out if these combined compounds would make a homogenous solution or not. Then write which IMF they have. 

CCl4 and H2O 

KCl and H2O 

1. heterogenous. H2O= london, Hbond CCl4= nonpolar

2. homogenous. london, dipole-dipole, H bond, ion-dipole

300

Nitrogen has a normal boiling point of 77.3 K and a melting point (at 1 atm) of 63.1 K. Its critical temperature is 126.2 K and its critical pressure is 2.55 x 104 torr. It has a triple point at 63.1 K and 94.0 torr. Sketch the phase diagram for nitrogen. Does nitrogen have a stable liquid state at 1 atm?

What is yes?

400

How much heat (in kJ) is required to warm 10.0 g of ice, initially at -10.0oC, to steam at 110.0oC? The heat capacity of ice is 2.09 J/g*oC, and that of steam is 2.01 J/g*oC.

What is 30.5kJ?

500

List the substances BaCl2, H2, CO, HF, and Ne in order of increasing boiling points and explain how you arrived at your answer.

BaCl2 > HF > CO > Ne > H2

Barium chloride is ionic (ionic bonding is stronger than any form of IMF), HF is second because of its hydrogen bonding.  CO > Ne >H2 because larger mass = more dispersion = stronger attraction to overcome to reach boiling point.