New Year 2017 teaching M1 add math/m2 add sci

A new year begins with classes in M1 Add Math and M2 Add Sci.  I asked to teach M1 to get more debaters for next year, but this year our school has three sections of M1 and M2--thus after hiring more upper Bio and Chem teachers--The G has moved down to lower school.

ASDC high lights--a traditionally difficult tournament--with National teams from various countries--older kids also, we took

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.