Silom Team Tennis: G/Nok vs Wat/Ying pt 2 2017

PHS M5 hw 2/10/17

1. The concentration of either the H⁺ ion or the OH⁻ ion is given for four aqueous solutions at 298 K. For each solution, calculate [H⁺] or [OH⁻]. State whether the solution is acidic, basic, or neutral.

a. [H⁺] = 1.0 × 10⁻¹³M

b. [OH⁻] = 1.0 × 10⁻⁷M

c. [OH⁻] = 1.0 × 10⁻³M

d. [H⁺] = 4.0 × 10⁻⁵M

2. Challenge Calculate the number of H⁺ ions and the number of OH⁻ ions in 300 mL of pure water at 298 K.

 READING CHECK Explain why you cannot obtain the [H⁺] directly from the molarity of a weak acid solution.

1. Calculate the pH of solutions having the following ion concentrations at 298 K.

a. [H⁺] = 1.0 × 10⁻²M

b. [H⁺] = 3.0 × 10⁻⁶M

2. Calculate the pH of aqueous solutions with the following [H⁺] at 298 K.

a. [H⁺] = 0.0055M

b. [H⁺] = 0.000084M

3. Challenge Calculate the pH of a solution having [OH⁻] = 8.2 × 10⁻⁶M.

sample Mr. Gary

Find youtube video-- predator or prey or predator eating prey--nothing gross
click share
click embed
ctrl C
go to blogger
click HTML
Ctrl V
post in sheets what your topic is

discuss three adaptations--for example orcas are big, fast, and have teeth

Multicolored electrolysis

Multicolored Electrolysis

acid and bases indicators electrolysis

Materials: petri dish universal indicator solution sodium chloride, NaCl, small amount 9 volt battery electrode wires with alligator clips (preferable red and black)

Procedure:

1.       two pencils sharpened at both ends, or two paper clips distilled water—take pictures.

2.       Fill a petri dish with distilled water.

3.       Add a small amount of salt and stir until dissolved.  —take pictures

4.       Add enough universal indicator to give a rich green color —take pictures.

5.       Attach each of the wire alligator clips to one end of each pencil lead. Attach the other ends of the electrodes to the battery poles, the red wire to the positive pole, the black wire to the negative pole. Turn the projector on.

6.       As electrolysis progresses, color changes will begin to occur.

7.       Place a niobium magnet in the middle and discuss what happens.

Discussion:

1.       Why is the universal indicator green when you first add it?

2.       Why can we use the pencils to run a charge.

3.       What is the color at the cathode?

4.       What is the color at the anode?

5.       What happens when you place the niobium magnet?  Why?

6.       What is the equation for the electrolysis of water? Without e and volts

7.       Why can we dump the solution down the drain?

Parent meeting

It was an impressive showing at the parent meeting as I ran out of handouts--I made 100 copies.   I ran out on the way to M5.  Really nice to see M6 parents one more time as they're about to graduate.  Gam has returned.

Giving alot of assessment this week with most levels having a quiz.

m1 biomes
m5 chem/bio have unit tests
m6 chem has their unit test

Should be a fun week before the long weekend

any questions please feel free to email me
gary

bonus

what fish are we using?  what species

M1 fish lab

1.  describe what happened in the experiment and propose an explanation for your observations.

2.  explain why some of the jars changed color.  the bromothymol blue will turn yellow in presence of carbon dioxide

3.  describe how plants and animals are dependent on each other.

4.  make a prediction about what will happen in one week.

5.  if anything happened, try to explain why.  sunlight causes the plants to give off oxygen