When a chemcial reaction occurs in a closed system, it will reach an equilibrium state in which reactants and products are produced at the same rate. This pathway provides resources to undestand the factors that affect chemical equilibrium.
Sal solves an example problem with rates with fractions. [5:06]
Khan Academy learning modules include a Community space where users can ask questions and seek help from community members. Educators should consult with their Technology administrators to determine the use of Khan Academy learning modules in their classroom. Please review materials from external sites before sharing with students.
Compare the cost of taking a shower with the cost of taking a bath. This interactive exercise focuses on using what you know about ratios to make a prediction about whether a shower or a bath is most cost effective and then requires completing the table to see if your prediction was accurate.
Water is essential for life as we know it, due in part to its ability to dissolve a wide range of substances. In fact, most chemical reactions occur in a dissolved state. This pathway provides resources regarding how water is able to act as a solvent.
Choosing how to present your talk is an important aspect of preparing for public speaking. Use these tips to decide the most effective method.
In this video segment from Cyberchase, Hacker and the CyberSquad race to reach the Good Vibration on staircases that grow at different rates and have steps of varying sizes.
When you are asked to make an object bigger or smaller, you will ask, "by how much?". In this case, scale factor can help answer the question. In this lesson, we will practice how to enlarge and reduce objects according to the scale factors given to us. A video tutorial is provided.
Students experientially learn about the characteristics of a simple physics phenomenon the pendulum by riding on playground swings. They use pendulum terms and a timer to experiment with swing variables. They extend their knowledge by following the steps of the engineering design process to design timekeeping devices powered by human swinging.
Students are introduced to the health risks caused by cooking and heating with inefficient cook stoves inside homes, a common practice in rural developing communities. Students simulate the cook stove scenario and use the engineering design process, including iterative trials, to increase warmth inside a building while reducing air quality problems. Students then collect and graph data, and analyze their findings.
Students overlay USGS topographic maps into Google Earth’s satellite imagery. By analyzing Denali, a mountain in Alaska, they discover how to use map scales as ratios to navigate maps, and use rates to make sense of contour lines and elevation changes in an integrated GIS software program. Students also problem solve to find potential pathways up a mountain by calculating gradients.
Students investigate rates and percentages by identifying the rates associated with a ratio, defining a percent as a rate per 100, and applying strategies to solve rate and percent problems.
Student centered activities based on rates and unit rates!
Find a quick, concise explanation of rates and ratios. Examples are given and clearly explained.
This tutorial shows how to use the information given in a table to find the rate of change between the values in the table. [3:46]
Check out this tutorial to practice finding the rate of change using a graph. [4:51]
Students study the physical properties of different fluids and investigate the relationship between the viscosities of liquid and how fast they flow through a confined area. Student groups conduct a brief experiment in which they quantify the flow rate to understand how it relates to a fluid's viscosity and ultimately chemical composition. They explore these properties in milk and cream, which are common fluids whose properties (and even taste!) differ based on fat content. They examine control samples and unknown samples, which they must identify based on how fast they flow. To identify the unknowns requires an understanding of the concept of viscosity. For example, heavy cream flows at a slower rate than skim milk. Ultimately, students gain an understanding of the concept of viscosity and its effect on flow rate.
This site is an example of the use of exponential decay. The example involves the effectiveness of a medical dosage over time.