Related questions with answers

In a probability experiment, a 1-6 number cube is rolled once. Find the theoretical probability (P) of each event. Express your answer as a fraction in simplest form. P (prime number)

Tris (hydroxymethyl)aminomethane, commonly called TRIS or Trizma, is often used as a buffer in biochemical studies. Its buffering range is from pH 7 to $9 ,$ and $K _ { b }$ is $1.19 \times 10 ^ { - 6 }$ for the reaction

\begin{array} {l}{{\left( \mathrm { HOCH } _ { 2 } \right) _ { 3 } \mathrm { CNH } _ { 2 } ( a q ) + \mathrm { H } _ { 2 } \mathrm { O } ( l ) \rightleftharpoons \left( \mathrm { HOCH } _ { 2 } \right) _ { 3 } \mathrm { CNH } _ { 3 } ^ { + } ( a q ) + \mathrm { OH } ^ { - } ( a q )} \\\quad {\text{TRIS}\quad \quad \quad \quad \quad \quad \quad \quad \quad \quad \quad \quad \quad \text{TRISH}^+}} \end{array}

A buffer is prepared by diluting 50.0 g of TRIS base and 65.0 g of TRIS hydrochloride (written as TRISHCl to a total volume of 2.0 L. What is the pH of this buffer? What is the pH after 0.50 mL of 12 M HCl is added to a 200.0-mL portion of the buffer?