Plan Investigations Mixing Substances
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5th Grade Science › Plan Investigations Mixing Substances
Students want to find out if mixing baking soda and vinegar makes something new. Their plan says: Purpose—watch for bubbles (gas) and temperature change. Materials—baking soda, vinegar, 2 clear cups, 1 tsp spoon, thermometer, tray, paper towels. Safety—Wear goggles, no tasting, wash hands after. Procedure: 1) Measure 2 tbsp vinegar into a cup and record its temperature. 2) Add 1 tsp baking soda and stir. 3) Record bubbles and temperature for 1 minute. What observation would provide the best evidence that a new substance formed?
Students should only record the color of the vinegar before mixing.
Students should taste the mixture to see if it tastes different than vinegar.
Students should check whether bubbles form and whether the mixture gets cooler or warmer.
Students should decide the reaction happened because they predicted it would happen.
Explanation
This question tests a 5th grader's ability to plan and carry out investigations that mix substances (NGSS 5-PS1-4), specifically observations. When planning a mixing investigation, students need to observe before and after to detect changes like gas production or temperature shifts that indicate a new substance. For this question, investigating whether baking soda and vinegar create new substance. Choice B is correct because it recognizes the need to observe bubbles and temperature changes. This shows the student understands before/after comparison shows change. Choice A represents a common error where students suggest tasting to observe, skipping safety rules. This typically happens because elementary students may prioritize excitement of mixing over safety. To help students: Use investigation checklist (question-materials-safety-procedure-recording). Watch for: Students who underestimate importance of safety rules.
Students want to find out if mixing baking soda and vinegar creates a new substance. Amir’s plan says: Purpose—see what happens when 1 tbsp baking soda is mixed with 30 mL vinegar in a clear cup. Safety—wear goggles, no tasting, and work on a tray. Procedure—(1) Observe each substance before mixing. (2) Mix and watch for bubbles and temperature change. (3) Record observations in a data table and clean up. Which observation would provide the best evidence that a new substance formed?
Students should record that bubbles of gas form right after mixing and the mixture gets foamy.
Students should record that the vinegar smells sour before mixing and still smells sour after mixing.
Students should record that the cup is clear so they can see the mixture.
Students should record that the baking soda is a white powder before mixing.
Explanation
This question tests 5th grader's ability to plan and carry out investigations that mix substances (NGSS 5-PS1-4), specifically identifying observations that provide evidence of chemical change. When planning a mixing investigation, students need to recognize that new substances form when we observe signs like gas production, temperature change, color change, or precipitate formation. For this question, mixing baking soda and vinegar creates carbon dioxide gas, which appears as bubbles and foam. Choice B is correct because it identifies the key observable evidence of a chemical reaction - the formation of gas bubbles and foam that weren't present in either original substance. This shows the student understands that new substances have different properties than the starting materials. Choice A represents a common error where students focus on properties that don't change (the vinegar still smells sour) rather than looking for new properties that appear. This typically happens because elementary students may not yet distinguish between physical properties that persist and new properties that indicate chemical change. To help students: Model identifying evidence of chemical change by having them list properties before and after mixing, then circle any NEW properties that appear. Watch for: Students who think any observation counts as evidence rather than focusing on changes that indicate new substance formation.
To investigate whether mixing creates a new substance, Maya mixes yeast, sugar, and warm water. Her steps are: 1) Mix 1 tsp yeast, 1 tsp sugar, and 1/2 cup warm water in a clear cup. 2) Watch for 10 minutes. 3) Write down what happens.
What should Maya do first to make her investigation plan stronger?
She should clean up all materials first so the table is empty.
She should taste the mixture to check if it is still sweet.
She should add random extra sugar each minute to speed up changes.
She should observe and record what each substance looks like before mixing.
Explanation
This question tests a 5th grader's ability to plan and carry out investigations that mix substances (NGSS 5-PS1-4), specifically the procedure for baseline observations. When planning a mixing investigation, students need to include clear questions, gather appropriate materials, follow safety rules, observe before and after, and record systematically. For this question, the specific context is investigating whether mixing yeast, sugar, and water creates a new substance through changes like bubbling. Choice B is correct because it follows a logical order of observe-mix-observe-record by starting with recording appearances before mixing for comparison. This shows the student understands that before/after comparison shows change and provides evidence of reactions. Choice D represents a common error where students suggest tasting the mixture to check properties like sweetness, skipping safety precautions. This typically happens because elementary students may prioritize excitement of mixing over safety and not yet understand that tasting can introduce risks or bias observations. To help students: Model planning with simple investigations like sugar in water before complex ones, emphasizing the step of 'observe before mixing' to establish a baseline. Watch for: Students who jump to mixing without planning, as they might forget to record initial states and lose the ability to compare changes.
Emma’s notebook entry says: Question—“What happens when we mix 1 tbsp baking soda with 30 mL lemon juice?” Prediction—“I think it will get fizzy.” Procedure: 1) Mix the substances in a cup. 2) Clean up the table. 3) Record what happened.
Which step should come right after mixing the substances to follow a good procedure order?
Put the cup away without looking so the reaction can finish in private.
Clean up immediately so nothing spills, and then decide what happened.
Add more lemon juice each minute until the cup is full.
Observe and record changes like bubbles and temperature before cleaning up.
Explanation
This question tests a 5th grader's ability to plan and carry out investigations that mix substances (NGSS 5-PS1-4), specifically the logical order in procedures. When planning a mixing investigation, students need to include clear questions, gather appropriate materials, follow safety rules, observe before and after, and record systematically. For this question, the specific context is investigating what happens when mixing baking soda and lemon juice. Choice B is correct because it follows a logical order of observe-mix-observe-record by noting changes like bubbles and temperature right after mixing. This shows the student understands that before/after comparison shows change and recording should happen before cleanup. Choice A represents a common error where students clean up first, potentially missing key observations during the reaction. This typically happens because elementary students may prioritize tidiness over systematic observation, thinking they can remember without immediate recording. To help students: Model planning with a checklist for procedure order, like mix-observe-record-clean, using examples like fizzy reactions. Watch for: Students who try to conclude before observing fully, jumping to cleanup and losing evidence of changes.
The investigation plan shows Chen comparing two mixtures: Cup 1 has 1 tsp baking soda + 2 tbsp vinegar. Cup 2 has 1 tsp baking soda + 2 tbsp water. Students will count bubbles for 30 seconds. Why is Cup 2 included?
Cup 2 is included so students can practice stirring before the real test.
Cup 2 is included to show what happens when baking soda is mixed with water only.
Cup 2 is included so students can taste it safely after the investigation.
Cup 2 is included to make sure both cups have different amounts of baking soda.
Explanation
This question tests a 5th grader's ability to plan and carry out investigations that mix substances (NGSS 5-PS1-4), specifically procedure. When planning a mixing investigation, students need to include controls for fair tests. For this question, comparing baking soda with vinegar vs water. Choice B is correct because it follows logical order of observe-mix-observe-record with a control cup. This shows the student understands proper materials enable observations. Choice C represents a common error where students include tasting, ignoring safety. This typically happens because elementary students may not connect materials to specific observations needed. To help students: Practice identifying what makes a good testable question. Watch for: Students who think conclusion should match prediction.
The investigation plan shows Fatima testing food coloring in water. Procedure: 1) Put 1/2 cup water into a clear cup. 2) Add 2 drops of food coloring. 3) Observe for 2 minutes and record changes. If Fatima wants to repeat the test to be sure of her results, what should she keep the same each time?
She should switch to a different cup size every time and not measure.
She should change the amount of water each time to get more interesting results.
She should record only the final color and skip observing during mixing.
She should keep the amount of water and number of drops the same each trial.
Explanation
This question tests a 5th grader's ability to plan and carry out investigations that mix substances (NGSS 5-PS1-4), specifically procedure. When planning a mixing investigation, students need to keep variables constant for repeatability. For this question, investigating food coloring diffusion in water. Choice A is correct because it includes keeping amounts the same for fair comparison. This shows the student understands investigations need clear purpose. Choice B represents a common error where students change variables randomly. This typically happens because elementary students may not yet understand importance of baseline observations. To help students: Model planning with simple investigation like sugar in water before complex ones. Watch for: Students who observe but don't record systematically.
Keisha is mixing cabbage juice (purple) with other substances to see color changes. Her plan says: “Put 2 tbsp cabbage juice in two cups. Add 1 tbsp vinegar to Cup 1 and 1 tsp baking soda mixed with 1 tbsp water to Cup 2. Observe.” How should Keisha record her observations so she can compare results clearly?
Keisha should taste each cup to decide which one is more acidic.
Keisha should write a data table with ‘Before Mixing,’ ‘During Mixing,’ and ‘After Mixing’ for each cup.
Keisha should clean up right after mixing so the colors do not change.
Keisha should only remember the colors in her head and share them later.
Explanation
This question tests 5th grader's ability to plan and carry out investigations that mix substances (NGSS 5-PS1-4), specifically creating organized recording systems for observations. When planning a mixing investigation, students need to create data tables or recording sheets that capture observations at key time points - this allows for clear comparisons and prevents forgetting important details. For this question, Keisha needs to track color changes in multiple cups over time. Choice B is correct because it describes a systematic data table with columns for different time points ('Before Mixing,' 'During Mixing,' 'After Mixing') for each cup, enabling clear comparison of how each substance affects cabbage juice color. This shows the student understands that organized recording systems are essential for tracking multiple trials. Choice A represents a common error where students rely on memory rather than written records. This typically happens because elementary students often overestimate their ability to remember details and may not yet value systematic documentation. To help students: Provide data table templates for investigations and model filling them out in real-time, showing how tables help us see patterns across multiple trials. Watch for: Students who think they can remember everything or who create disorganized notes that make comparison difficult later.
The investigation plan shows Maya mixing 1 tbsp salt with 1/2 cup water to see how fast salt dissolves. Materials listed: salt, water, 3 clear cups, 1 tsp spoon, timer, tray. Safety: No tasting and wash hands. Procedure: 1) Put 1/2 cup water in each cup. 2) Add 1 tbsp salt and stir 10 times. 3) Write what you see after 30 seconds. What is missing that would make this a fair test for “how fast” the salt dissolves?
Students should taste the water to check if the salt is still there.
Students should use a different amount of water in each cup to compare more results.
Students should record the time it takes until the salt is no longer visible in each cup.
Students should use a magnifying glass to look at the salt grains up close.
Explanation
This question tests a 5th grader's ability to plan and carry out investigations that mix substances (NGSS 5-PS1-4), specifically procedure. When planning a mixing investigation, students need to follow logical order of observe-mix-observe-record. For this question, comparing salt dissolving. Choice C is correct because it includes recording time for dissolving, making it a fair test for speed. This shows the student understands proper procedure enables observations. Choice B represents a common error where students suggest tasting to check, forgetting safety. This typically happens because elementary students may not yet understand importance of baseline observations. To help students: Model planning with simple investigation like sugar in water before complex ones. Watch for: Students who observe but don't record systematically.
Chen is planning an investigation: “What happens when I mix sand and water?” Materials: sand, water, 2 clear cups, 1 tsp measuring spoon. Procedure: (1) Put 1 tsp sand in a cup. (2) Add 1/2 cup water and stir. (3) Watch for 3 minutes. What is missing from Chen’s plan that would make the investigation better?
Chen should add food coloring so the water turns a brighter color.
Chen should use a different amount of sand each time to make it more exciting.
Chen should taste the sand-water mixture to see if it is salty.
Chen should record observations before, during, and after mixing in writing or a table.
Explanation
This question tests 5th grader's ability to plan and carry out investigations that mix substances (NGSS 5-PS1-4), specifically the importance of systematic observation and recording. When planning a mixing investigation, students need to document what they observe at each stage - before mixing (baseline), during mixing (process), and after mixing (results) - to track changes and draw conclusions. For this question, Chen's procedure observes the mixing but lacks any recording system. Choice B is correct because it identifies the critical missing element: a system for recording observations at multiple time points, either through written notes or a data table. This shows the student understands that science requires documentation, not just watching. Choice C represents a common error where students suggest tasting the mixture, violating basic safety rules. This typically happens because elementary students may default to using all their senses without considering safety restrictions in scientific investigations. To help students: Provide observation templates with columns for 'Before,' 'During,' and 'After' to scaffold systematic recording, and model how to describe observations using scientific vocabulary. Watch for: Students who think they can remember everything without writing it down or who only record final results without documenting the process.
To investigate whether mixing oil and water makes a mixture that stays mixed, Carlos wrote this procedure: 1) Pour 1/2 cup water into a clear jar. 2) Add 2 tbsp oil and put the lid on tightly. 3) Shake for 10 seconds and observe. Which measurement should Carlos record to best answer his question?
How long it takes for the oil and water to separate into two layers after shaking.
Whether the jar is made of glass or plastic.
What the oil tastes like compared to the water.
How many times he can shake the jar before his arms get tired.
Explanation
This question tests a 5th grader's ability to plan and carry out investigations that mix substances (NGSS 5-PS1-4), specifically recording. When planning a mixing investigation, students need to record systematically. For this question, investigating whether oil and water stay mixed. Choice A is correct because it follows logical order of observe-mix-observe-record by measuring separation time. This shows the student understands recording creates evidence. Choice C represents a common error where students suggest tasting, ignoring safety. This typically happens because elementary students may prioritize excitement of mixing over safety. To help students: Emphasize that science is observing what actually happens, not proving we're right. Watch for: Students who think conclusion should match prediction.