Matter is not created nor destroyed; it simply changes from one form to another. This law of conservation of mass challenges elementary students’ ideas about matter, because many children may think that matter is created or destroyed in a chemical reaction. In this lesson, students will challenge their preconceptions about matter by experimenting with physical and chemical changes to determine that the total weight of the matter does not change. Students will use math to show that the total weight of matter is equal to the sum of the weight of its component parts, and they will graph this information to show that the weight of matter is conserved during physical and chemical changes.
This lesson results from a collaboration between the Alabama State Department of Education and ASTA.
In this lesson, students will be able to make measurements showing that whether the process is a change of state, dissolving, or a chemical reaction, the total mass of the substances does not change. Students check to see whether the mass of ice and water in a cup changes as the ice melts. Students also test whether the combined mass of sugar and water changes after sugar is dissolved in the water. As a demonstration, students will observe that a precipitate forms in a reaction between solutions of magnesium sulfate and sodium carbonate, and that the mass of the products is the same as the mass of the reactants.
In this lesson, students explore the interaction of two substances and see that they can use what they know about the interaction of particles to explain their observations. Students place an M&M in water and see the colored sugar coating dissolve around the M&M. Students help develop a model to explain that the attraction of water molecules for sugar and color (dye) molecules is a good explanation for why the sugar coating dissolves. Students then test whether the coating dissolves as well in a sugar solution as it does in plain water. They put three or four different colored M&Ms together in water and watch the coatings dissolve. Students will see a distinct “line” where the colors meet. Students use molecular models to make an argument about why the dissolving M&Ms form a line.
In this lesson, students observe chemical reactions that produce obvious effects (as opposed to reactions in which the substances appear not to change at all). They begin by exploring a different substance every day for one week. They compare the substances and learn that substances can be solids, liquids, or gases. Next, through teacher demonstration (or direct, supervised student involvement), students watch what happens when sand and water are mixed together (no chemical reaction), and when several pairs of acids and bases are mixed together (a chemical reaction occurs). Students then get to build their own "film canister rockets," using baking soda and vinegar as rocket fuel. This lesson concludes with open-ended thinking when students are asked to determine where rust comes from.
A scientific theory is a proposed description, explanation, or model of something occurring in nature. These theories have to be testable so that scientists can use the scientific method to see if they work.
The classroom resource provides a video that will introduce students to the scientific method, developing hypotheses, and collecting evidence. There is a karaoke song that students can learn to help them remember the steps in the scientific method. Students can use the information presented in this video to follow the scientific method as they plan their own investigations. There is also a short test that can be used to assess students' understanding.
Scientists are always working to better understand the world. They use the scientific method to help them. The scientific method includes making observations, developing hypotheses, designing experiments, collecting data, and then drawing conclusions.
The classroom resource provides a video that will introduce students to the scientific method and experimentation. There is a karaoke song that students can learn to help them remember the steps in the scientific method. Students can use the information presented in this video to follow the scientific method as they plan their own investigations. There is also a short test that can be used to assess students' understanding.
When scientists conduct experiments, they collect data through observation and measurement. There are many different ways to measure data, but they all help ensure that scientists can collect accurate information.
The classroom resource provides a karaoke song that will describe how scientists collect data as they experiment. Students can use the information presented in this audio resource as they plan their own investigations. There is also a short test that can be used to assess students' understanding.
Physical changes mean matter changes size or shape, not its atomic makeup. Chemical and nuclear changes alter matter on an atomic level.
The classroom resource provides a video that will explain the difference between physical and chemical changes of matter. This resource can provide background information for students before they conduct their own investigations. There is also a short test that can be used to assess students' understanding.
Jump in with both feet as you watch oobleck (cornstarch and water mixture) videos and learn about three states of matter: solids, liquids, and gases. Learn to use captions and charts to make reading comprehension less messy and loads of fun.
Chocolate lovers, unite around this sweet interactive science lesson featuring a milk chocolate-loving cow. Melt chocolate and make fudge to learn about liquid and solid phases of matter. Read and record chocolate data using flowcharts and bar graphs.
The primary purpose of this experiment is to engage students in an activity that will allow them to observe that hotter conditions can speed up changes in materials. Students will predict whether food coloring disperses more quickly in hot, cold, or room temperature water, and then carry out a short activity to explore their predictions.