Buffers, the Acid Rain Slayer: Crash Course Chemistry #31

Learning Resource Type

Classroom Resource

Subject Area

Science

Grade(s)

9, 10, 11, 12

Overview

In this episode, Hank talks about how nutty our world is via buffers. He defines buffers and their compositions, talks about carbonate buffering systems in nature, acid rain, pH of buffers, and titration. Plus, a really cool experiment using indicators to showcase just how awesome buffers are.

Science (2015) Grade(s): 09-12 - Chemistry

SC15.CHM.6

Use mathematics and computational thinking to express the concentrations of solutions quantitatively using molarity.

UP:SC15.CHM.6

Vocabulary

  • Molarity
  • Moles
  • Volume
  • Solution
  • Solute
  • Solvent
  • Concentrations
  • Dissolving
  • Solubility
  • Ionic
  • Covalent
  • atomic/ molecular/ particulate level
  • macroscopic level
  • pH
  • hydronium ion
  • hydroxide ion
  • concentration
  • concentrated
  • dilute
  • acids and bases (strong/ weak)
  • properties

Knowledge

Students know:
  • The mole is used to convert between the atomic/ molecular and macroscopic levels.
  • Concentrations of solutions can be compared quantitatively using molarity.
  • Mathematical representations may include calculations, graphs or other pictorial depictions of quantitative information.
  • Solutions are a type of mixture that appears homogeneous at the macroscopic level but may be heterogeneous at the atomic/ molecular level.
  • Solutes are the portion of a solution present in the lesser amount.
  • Solvents are the portion of a solution present in the greater amount.
  • Both temperature and pressure affect the solubility of solutes.
  • The effect of temperature on the solubility of a liquid or solid solute differs from that of gaseous solutes.
  • The effect of pressure on the solubility of gaseous solutes differs from that of liquid or solid solutes.
  • The ability of a substance to conduct electricity is determined by the presence of charged particles that are able to move about freely.
  • Ionic compounds typically conduct electricity when melted or dissolved in water because the charged particles are able to move about freely.
  • Covalent compounds typically do not conduct electricty when melted or dissolved in water because there are no charged particles.
  • Exceptions to the typical conductivity of solutions include strong acids, which ionize in water solutions.
  • An acid has more hydronium ions than hydroxide ions.
  • A base has more hydroxide ions than hydronium ions. pH is a measure of the number of hydronium ions present in a solution.

Skills

Students are able to:
  • Identify solute and solvent in a solution.
  • Calculate the molarity of a solution.
  • Represent the process of dissolving using a model.
  • Analyze data using tools, technologies, and/ or models to identify relationships within the datasets.
  • Use analyzed data as evidence to describe the relationships between temperature changes and pressure changes on solubility.
  • Plan an investigation that outlines the experimental procedure, including safety considerations, how data will be collected, number of trials, experimental setup, and equipment required.
  • Conduct a planned investigation to test the conductivity of common ionic and covalent substances in solution.
  • Analyze collected and recorded data from investigation to determine conductivity of common ionic and covalent substances.
  • Use the pH scale to determine if a substance is acidic or basic.
  • Determine the concentration of hyfronium or hydroxide ions in a solution based on pH value.

Understanding

Students understand that:
  • Mathematical representations of phenomena are used to describe explanations.
  • The properties of matter at the macroscopic level are determined by the interaction of particles at the atomic/ molecular level.
  • Proportional relationships among different types of quantities provide information about the magnitude of properties.
  • Models are used to predict the relationships between systems or components of a system.
  • The properties of matter at the macroscopic level are determined by the interaction of particles at the atomic/ molecular level.
  • Proportional relationships among different types of quantities provide information about the magnitude of properties.
  • Data can be analyzed using tools, technologies, and/ or models (e.g., computational, mathematical) in order to make valid and reliable scientific claims.
  • Different patterns may be observed at each of the scales at which a system is studied and ca provide evidence for causality in explanations of phenomena.
  • The properties of matter at the macroscopic level are determined by the interaction of particles at the atomic/ molecular level.
  • Empirical evidence is required to differentiate between cause and correlation and make claims about specific causes and effects.
  • Scientists plan and conduct an investigation individually and collaboratively to produce data to serve as the basis for evidence, and in the design decide on types, how much, and accuracy of data needed to produce reliable measurements.
  • The properties of matter at the macroscopic level are determined by the interaction of particles at the atomic/ molecular level.
  • The function of a material and its macroscopic properties are related to the atomic/ molecular level structure of the material.
  • Models are used to predict the relationships between systems or components of a system.
  • The properties of matter at the macroscopic level are determined by the interaction of particles at the atomic/ molecular level.
  • Proportional relationships among different types of quantities provide information about the magnitude of properties.

Scientific and Engineering Practices

Developing and Using Models; Planning and Carrying out Investigations; Analyzing and Interpreting Data; Using Mathematics and Computational Thinking

Crosscutting Concepts

Patterns; Cause and Effect; Scale, Proportion, and Quantity; Structure and Function

CR Resource Type

Audio/Video

Resource Provider

PBS

License Type

Custom

Accessibility

Video resources: includes closed captioning or subtitles
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