Mix it up!
A gardener combines soil, small rocks, and pieces of bark in one pot. Together, these materials form this.
What is a mixture?
A backpack label says “made from nylon.” Nylon is this part of the backpack’s description.
What is its material?
A student examines a rock with a hand lens and notices tiny shiny spots. The student is practicing this science skill.
What is observing?
An orange contains citric acid. The citric acid belongs to this group of substances.
What are acids?
Red and blue beads sit in separate piles. To spread both colors throughout one container, a student must do this.
What is mix them?
A student chooses a stretchy band instead of string to launch a model car. This useful property explains the choice.
What is elasticity, or the ability to stretch and return to its shape?
A team needs to compare the masses of two clay samples. This tool will provide measurements in grams.
What is a balance or scale?
A bicycle develops rust after being left outside. Because rust is a new substance, its formation is this kind of change.
What is a chemical change or chemical reaction?
A student combines paper clips and rice. This tool can remove the paper clips without removing the rice.
What is a magnet?
A team needs a roof for a model house. Waxed paper keeps the inside dry, but a paper towel lets water through. This material is the better choice.
What is waxed paper?
One student writes, “The sponge feels rough.” Another writes, “The sponge is 8 centimeters long.” This statement records a measurement.
What is “The sponge is 8 centimeters long”?
A student tears aluminum foil into small pieces. This explains why tearing alone is not evidence of a chemical reaction.
What is the pieces are still aluminum, so no new substance formed?
A student claims that combining buttons and marbles creates a new substance. This observation shows that the materials kept their original properties.
What is the buttons and marbles can still be recognized and separated?
Two white powders look alike. One dissolves in water, and the other does not. Students can use this difference to help do this.
What is identify the substances?
A team claims Cloth A absorbs more water than Cloth B. In three fair tests, Cloth A absorbs 20 milliliters each time, while Cloth B absorbs 8 milliliters each time. These results serve this role in the team’s explanation.
What is evidence supporting the claim?
Purple cabbage indicator turns pink in a known acid. A mystery liquid also turns the indicator pink under the same conditions. This is a reasonable conclusion about the mystery liquid.
What is it is likely acidic?
A student crushes chalk and mixes it with sand. The student says crushing and mixing prove a chemical reaction happened. This missing evidence would be needed to support that claim.
What is evidence that a new substance formed?
A student says color alone will identify every metal object. Two different metals are both silver-colored. This next step would make the identification stronger.
What is test another property, such as attraction to a magnet?
A student claims a mystery powder dissolves completely. After stirring, grains remain at the bottom in every trial. This is how the evidence affects the claim.
What is it does not support the claim because some powder remains undissolved?
An engineer investigates why an iron fence rusts and tests coatings that might prevent the reaction. The engineer is applying this field of science.
What is chemistry?