STAAR Science Category 2

Which of the following is an example of a chemical reaction?

• A marshmallow turning black when heated over a fire

• A powder dissolving in water to make lemonade

• An ice cube melting into a puddle of water

• Salt crystals being crushed into a powder
  

Tags

NGSS.MS-PS1-2

How many neutrons does the an element with an atomic number of 3 and a mass of 6.9 contain?

Tags

NGSS.MS-PS1-1

Look at the picture abov. Beased on this picture, why do the North and South poles of the Earth have much longer periods of light and darkness than the rest of the planet?

• The poles are angled toward or away from the Sun because of Earth's revolution.

• The rotation of the Earth is fast enough to keep the poles lit all the time.

• The Moon is closest to the poles, so it keeps those areas colder and darker.

• The Sun can never reach the poles because of the way the Earth is tilted.

Tags

NGSS.MS-ESS1-1

A student wants to use a spinning basketball to model the day-and-night cycle on Earth. What should the student do in order to best model the cause of the day-and-night cycle?

• Spin the ball in different directions

• Tilt the ball while it is spinning

• Paint one half of the ball black and the other half white

• Shine a bright light on one side of the ball

Tags

NGSS.MS-ESS1-1

The diagram shows four positions in Earth’s orbit around the sun. The Northern Hemisphere experiences the beginning of spring when Earth is in —

• Position 1

• Position 2

• Position 3

• Position 4

Tags

NGSS.MS-ESS1-1

Students in a science class in Marfa, Texas, made a poster with a diagram to represent a seasonal change in the Northern Hemisphere. Which statement best describes conditions for Earth at Position 1 in the diagram?

• Earth’s orbit around the sun is not a perfect circle.

• North America has a larger landmass than South America.

• The moon has a greater pull on South America than on North America.

• Earth’s axis has a 23.5° tilt.

Tags

NGSS.MS-ESS1-1

The moon reflects different amounts of sunlight onto Earth at different times. This reflected sunlight is commonly called moonlight. The graph below shows the intensity of moonlight at different times in a lunar cycle. Which moon phase most likely occurs at the time in the cycle represented by an X on the graph?

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Tags

NGSS.MS-ESS1-1

Two stars are identified on the Hertzsprung-Russell diagram below. Based on this diagram, how do the characteristics of Star 1 and Star 2 compare?

• Star 1 is cooler and less bright than Star 2.

• Star 1 is hotter and brighter than Star 2.

• Star 1 is cooler and brighter than Star 2.

• Star 1 is hotter and less bright than Star 2.

The Hertzsprung-Russell diagram below shows how the brightness, surface temperature, and color of stars are related. Which of these observations of Barnard’s Star is most likely accurate?

• Barnard’s Star is less bright than the sun, has a surface temperature below 3,800 K, and is red.

• Barnard’s Star is less bright than the sun, has a surface temperature above 3,800 K, and is red.

• Barnard’s Star is brighter than the sun, has a surface temperature below 5,300 K, and is yellow.

• Barnard’s Star is brighter than the sun, has a surface temperature above 5,300 K, and is yellow.

Most stars in the universe fit into one of the four areas on this Hertzsprung-Russell diagram. Which area of the diagram represents the white dwarfs?

• Star 1

• Star 2

• Star 3

• Star 4