01
Choose one
1 point
Which example is a physical change rather than a chemical change?
Free Practice Quiz Question List
07 Chemistry and Scientific Reasoning Online Quiz Questions
Use this free practice quiz with 20 questions to review 07 Chemistry and Scientific Reasoning, test your knowledge, and prepare for your next test or exam.
20 questions
02
True or false
1 point
True or false: In science, a theory is merely a guess that has not been tested with evidence.
- A
True
- B
False
03
True or false
1 point
True or false: Observing bubbles is sufficient by itself to prove that a chemical reaction occurred.
- A
True
- B
False
04
Fill in the blank
1 point
During a chemical reaction, atoms are rearranged, not .
05
Fill in the blank
1 point
When appropriate, a control group or condition provides a that does not receive the tested treatment.
06
Written response
1 point
A sample has a mass of 18 g and a volume of 6 mL. What is its density? Give the numerical value in g/mL.
07
Written response
1 point
In an experiment testing how water temperature affects an effervescent tablet’s dissolving time, which factor is deliberately changed?
08
Choose one
1 point
A pure sample of water consists of hydrogen and oxygen chemically combined in a fixed ratio. How should the sample be classified?
- A
An element
- B
A heterogeneous mixture
- C
A compound
- D
A homogeneous mixture
09
Choose one
1 point
A tablet’s mean dissolving times at 20 °C, 40 °C, and 60 °C were 90 s, 55 s, and 32 s, respectively. Which conclusion is directly supported by these results?
- A
The mean dissolving time was shorter at higher tested water temperatures.
- B
The mean dissolving time was longer at higher tested water temperatures.
- C
The mean dissolving time was the same at every tested temperature.
- D
The data show that tablet type caused the differences.
10
Choose all
1 point
Select all observations that may be evidence of a chemical change, while recognizing that an observation alone is not automatic proof.
- A
Gas formation during a process
- B
A lasting color change
- C
A change in the shape of a solid with no other change
- D
Formation of an insoluble solid
11
Choose all
1 point
To test whether water temperature affects an effervescent tablet’s dissolving time, select all conditions that should be kept consistent across trials.
- A
Use the same tablet type in each trial.
- B
Use the same water volume in each trial.
- C
Use a different water temperature in each trial.
- D
Stir each sample in the same way, including not stirring any of them.
12
Choose one
1 point
A scientist uses a general explanation to derive a specific prediction to test. Which kind of reasoning is being used?
- A
Inductive reasoning
- B
Random sampling
- C
Deductive reasoning
- D
Measurement uncertainty
13
Open ended
1 point
Repeated measurements are very close to one another, but all are far from the accepted value. Explain whether the measurements are accurate, precise, both, or neither, and distinguish accuracy from precision.
14
True or false
1 point
True or false: Repeating trials can help reveal whether an observed pattern is consistent rather than due to chance variation.
- A
True
- B
False
15
Choose one
1 point
Which observation does not, by itself, prove that a chemical reaction occurred?
- A
Bubbles produced as water boils
- B
Atoms rearranging to form new substances
- C
A precipitate forming during a reaction
- D
A lasting color change caused by a reaction
16
Choose one
1 point
A student dissolves different amounts of salt in water, producing a uniform solution each time. How should the resulting salt water be classified?
- A
A pure sample of iron
- B
A pure sample of water with a fixed composition
- C
Salt dissolved uniformly in water
- D
A pure sample of oxygen
17
Choose one
1 point
In an experiment, a student uses the same type of effervescent tablet, water volume, and container, but varies the water temperature and measures dissolving time. What is the independent variable?
- A
The tablet’s dissolving time
- B
The water temperature
- C
The water volume kept the same
- D
The tablet type kept the same
18
Written response
1 point
A sample has a mass of 12 g and a volume of 4 mL. What is its density? Enter the numerical value in g/mL.
19
Choose one
1 point
A student wants to test whether water temperature affects how quickly an effervescent tablet dissolves. Which design best isolates the effect of temperature?
- A
Use the same tablet type, water volume, and container; change only temperature and do not stir the samples differently.
- B
Use different tablet types at each temperature and keep water volume constant.
- C
Change both temperature and water volume while using the same tablet type.
- D
Use the same temperature for every sample but change the container and stirring method.
20
Written response
1 point
A scientist notices the same pattern across several specific observations and uses it to propose a broader generalization. What type of reasoning is this?