First Five for January 26 and 27

Balance each of the following equations:

____C3H8   +   ____O2       →            ____CO2    +    ____H2O

____C5H12   +   ____O2         →          ____CO2    +    ____H2O

____C4H10   +   ____O2        →           ____CO2    +    ____H2O

____C2H2   +   ____O2         →          ____CO2    +    ____H2O

January 26th, 2012 | Category: Chemistry, First Five | Comments are closed

AP Chemistry Warm-up for January 26

Review Problem

A compound is found to be composed of 40.0% carbon by mass, 6.7% hydrogen by mass, with the remainder being oxygen. 

  • What is the empirical formula of the compound?

  • The molar mass is estimated at 180 g/mol. What is the molecular formula of the compound?

January 26th, 2012 | Category: AP Chemistry, AP Chemistry Warmup | Comments are closed

AP Chemistry Warm-up for January 24

Reaction Problem

  • Chlorine gas is bubbled through an aqueous solution of  potassium bromide.

  • What other halogens could perform the same role as chlorine in this reaction?

January 24th, 2012 | Category: AP Chemistry, AP Chemistry Warmup | Comments are closed

First Five for January 24 and 25

Draw electron dot notations for the following elements:

  • potassium (K)

  • fluorine (F)

  • carbon (C)

  • phosphorus (P)

  • selenium (Se)

January 24th, 2012 | Category: Chemistry, First Five | Comments are closed

First Five for January 23

1. Place the following elements in order from largest radius to smallest radius.

beryllium, strontium, barium, calcium, magnesium

2. Place the elements above in order from the largest ionization energy to the smallest ionization energy

January 23rd, 2012 | Category: Chemistry, First Five | Comments are closed

AP Chemistry Warm-up for January 23

Review Problem

  • Describe the process for producing 500.0 mL of 1.5 M H2SO4 aqueous solution from concentrated sulfuric acid (98%, or 18.4 M).

  • Do you add water to the concentrated acid, or concentrated acid to water? Why?

January 23rd, 2012 | Category: AP Chemistry, AP Chemistry Warmup | Comments are closed

First Five for January 19 and 20

Match the elements at right with the element class to which they belong on the left.

Class:

  • Halogen 

  • Nonmetal 

  • Transition metal 

  • Alkali metal 

  • Noble gas 

  • Alkaline Earth metal

  • Metalloid (Semimetal)

  1. Argon (#18) 

  2. Palladium (#46)

  3. Phosphorus (#15)

  4. Potassium (#19)

  5. Arsenic (#33)

  6. Strontium (#38)

  7. Iodine (#53)

  8. Titanium (#22)
January 19th, 2012 | Category: Chemistry, First Five | Comments are closed

AP Chemistry Warm-up for January 19

Reaction Problem

  • Solid potassium hydroxide is added to a solution of nitric acid

  • Would you expect the process to be endothermic or exothermic?

January 19th, 2012 | Category: AP Chemistry, AP Chemistry Warmup | Comments are closed

AP Chemistry Warm-up for January 17

Review Problem

  • A 5.00 gram piece of dry ice (CO2) is placed in a sealed 10.0 L container at a temperature of 25°C and allowed to sublime. If the pressure before sublimation was 1.01 atm (due to the air in container), what is the final pressure in the container after sublimation, assuming the temperature remains constant?

  • Why is it most unlikely that the temperature inside the container remains constant during sublimation? Should the final temperature be higher or lower than the initial temperature of 25°C?

January 17th, 2012 | Category: AP Chemistry, AP Chemistry Warmup | Comments are closed

First Five for January 17 and 18

Match the descriptors at left with the appropriate particle(s) on the right.

Descriptors:

  • Mass# = 1

  • Mass# = 0

  • Positive

  • Negative

  • Neutral

  • found in the nucleus

  • found outside the nucleus

  1. Electron

  2. Proton

  3. Neutron
January 17th, 2012 | Category: Chemistry, First Five | Comments are closed
 
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