2.9 Test Review

Identify the variable that is changed in an experiment.

• Dependent variable

• Independent variable

• Control

Answer explanation

The independent variable is the one that is changed or manipulated in an experiment to observe its effect on the dependent variable. It is crucial for testing hypotheses.

Tags

NGSS.MS-PS2-2

Identify the variable that changes because of the changing the independent variable.

• Dependent variable

• Independent variable

• Control

Answer explanation

The dependent variable is the one that changes in response to the independent variable. In experiments, it is measured to see how it is affected by variations in the independent variable.

Tags

NGSS.MS-LS1-5

Identify the variable(s) that remains the same in an experiment.

• Dependent variable

• Independent variable

• Control

Answer explanation

In an experiment, the control variables are the factors that remain constant to ensure a fair test. Unlike the dependent and independent variables, which change, controls help isolate the effect of the independent variable.

Where does the temperature go on a graph when plotting temperature versus time?

• Temperature is on the y-axis.

• Temperature is on the x-axis.

• Temperature is on the origin.

• Temperature is not plotted.

Answer explanation

In a graph plotting temperature versus time, temperature is typically represented on the y-axis, while time is on the x-axis. This allows for a clear visualization of how temperature changes over time.

Tags

NGSS.MS-PS3-1

Where does time go on a graph when plotting temperature versus time?

• Time is on the x-axis.

• Time is on the y-axis.

• Time is in the legend.

• Time is in the title.

Answer explanation

In a graph plotting temperature versus time, time is conventionally placed on the x-axis. This allows for a clear representation of how temperature changes over time, making the correct choice 'Time is on the x-axis.'

How should a hypothesis be written?

• An educated guess; if/then format.

• A random statement with no evidence.

• A summary of results after the experiment.

• A list of materials used in the experiment.

Answer explanation

A hypothesis should be an educated guess that predicts an outcome, typically written in an if/then format. This structure allows for clear testing and validation of the hypothesis through experimentation.

Name one way scientists 'prove' their theory.

• Collect results from many different experiments.

• Make up data to fit their theory.

• Ignore evidence that contradicts their theory.

• Rely only on opinions.

Answer explanation

Scientists prove their theories by collecting results from many different experiments. This method ensures that findings are reliable and can be replicated, unlike making up data or ignoring contradictory evidence.

Tags

NGSS.MS-LS1-6

NGSS.MS-LS2-4

What type of graph is used to show percentages?

• Circle graph

• Bar graph

• Line graph

• Histogram

Answer explanation

A circle graph, or pie chart, is specifically designed to show percentages of a whole, making it the best choice for representing data in terms of parts of a total. Other graphs like bar or line graphs do not effectively convey percentage relationships.

Convert 861 mL to liters.

• 0.861 L

• 8.61 L

• 86.1 L

• 0.0861 L

Answer explanation

To convert milliliters to liters, divide by 1000. Thus, 861 mL ÷ 1000 = 0.861 L. Therefore, the correct answer is 0.861 L.

Calculate: 2.32 + 6.8 + 2.056

• 11.2

• 10.8

• 12.0

• 9.9

Answer explanation

To calculate 2.32 + 6.8 + 2.056, first add 2.32 and 6.8 to get 9.12. Then, add 2.056 to 9.12, resulting in 11.176, which rounds to 11.2. Thus, the correct answer is 11.2.