When food enters the stomach, HCl is released and the [H3O+] of the stomach fluid rises to 4 × 10–2 M. What is the pH of the stomach fluid?

Understand the relationship between [H₃O⁺] and pH. The pH of a solution is calculated using the formula: pH=-log([H3O]). This formula tells us that pH is the negative logarithm (base 10) of the hydronium ion concentration. Identify the given value for [H₃O⁺]. From the problem, the hydronium ion concentration is 4×10-2 M. Substitute the given [H₃O⁺] value into the pH formula. This gives: pH=-log(4×10-2). Break the calculation into two parts for clarity. First, use the logarithmic property: log(4×10-2)=log(4)+log(10-2). Then, recall that log(10-2)=-2. Combine the results. The pH is calculated as: pH=-(log(4)+-2). Simplify further to find the final pH value.

Ch.10 Acids and Bases and Equilibrium

Timberlake - Chemistry: An Introduction to General, Organic, and Biological Chemistry 14th Edition

Timberlake14th EditionChemistry: An Introduction to General, Organic, and Biological ChemistryISBN: 9781292472249당신이 사용하는 게 아니라요?교과서 변경

모든 교과서

Timberlake 14th Edition

Ch.10 Acids and Bases and Equilibrium

문제 64

10장, 문제 64

When food enters the stomach, HCl is released and the [H₃O⁺] of the stomach fluid rises to 4 × 10^–2 M. What is the pH of the stomach fluid?

검증된 단계별 안내

Understand the relationship between [H₃O⁺] and pH. The pH of a solution is calculated using the formula:

pH = - \log ({[H}_{3} O])

. This formula tells us that pH is the negative logarithm (base 10) of the hydronium ion concentration.

Identify the given value for [H₃O⁺]. From the problem, the hydronium ion concentration is

4 \times 10^{- 2}

Substitute the given [H₃O⁺] value into the pH formula. This gives:

pH = - \log (4 \times 10^{- 2})

Break the calculation into two parts for clarity. First, use the logarithmic property:

\log (4 \times 10^{- 2}) = \log (4) + \log (10^{- 2})

. Then, recall that

\log (10^{- 2}) = - 2

Combine the results. The pH is calculated as:

pH = - (\log (4) + - 2)

. Simplify further to find the final pH value.

비슷한 문제에 대한 검증된 영상 답변:

이 영상 해법은 위 문제에 도움이 된다고 튜터들이 추천한 것입니다.

영상 길이:

주요 개념

질문에 올바르게 답하기 위해 반드시 이해해야 하는 핵심 개념들은 다음과 같습니다.

pH Scale

The pH scale measures the acidity or basicity of a solution, ranging from 0 to 14. A pH of 7 is neutral, while values below 7 indicate acidity and above 7 indicate alkalinity. The scale is logarithmic, meaning each whole number change represents a tenfold change in hydrogen ion concentration.

Hydronium Ion Concentration

Hydronium ion concentration, represented as [H₃O⁺], indicates the amount of hydronium ions present in a solution. It is directly related to the acidity of the solution; higher concentrations correspond to lower pH values. In this case, a concentration of 4 x 10⁻² M indicates a significant level of acidity.

Calculating pH

To calculate pH, the formula pH = -log[H₃O⁺] is used, where [H₃O⁺] is the concentration of hydronium ions in moles per liter. This calculation allows us to determine the acidity of the solution quantitatively. For example, if [H₃O⁺] is 4 x 10⁻² M, the pH can be calculated to find the exact acidity level.