CBA #2 Review

Students are using samples of several different substances for an investigation. They will observe the physical properties of each substance and then record their observations.

Substance

  NaOH

Cu

H2O

H2

N2

Which of the substances observed are elements?

• NaOH, Cu, N2

• N2, Cu, H2

• Cu, H2, H2O

• H2O, N2, H2

Tags

NGSS.MS-PS1-1

Which of the following best describes what occurs after two elements are chemically joined together?

• A substance that is the same as the elements formed.

• A mixture is formed.

• The physical properties of the substance stays the same.

• A compound is formed.

Tags

NGSS.MS-PS1-1

A student uses colored beads to make a model of glucose (C6H12O6). The color of beads she uses for each element is shown on the table below.

Element Bead Color

Carbon Blue

Hydrogen Yellow

Oxygen Green

Which combination of beads should the student use for the model?

• 6 yellow, 12 green, and 6 blue

• 12 yellow, 6 blue, and 6 green

• 12 yellow, we blue, and 6 green

• 6 green, 6 yellow, and 6 blue

Tags

NGSS.MS-PS1-1

Which of the following correctly identifies the number of atoms in each element of the following compound?

H2SO4

• 2 Hydrogen, 1 Sulfur, 4 Oxygen

• 2 Hydrogen, 4 Sodium

• 1 Hydrogen, 2 Sulfur, 4 Oxygen

• 2 Hydrogen, 4 Oxygen

Tags

NGSS.MS-PS1-1

A student observes sugar as it is heated and burns and concludes that a chemical reaction has occurred. Which of the following observations provides evidence of a chemical reaction?

• Heat is added to the sugar crystals

• The temperature of the sugar is increased

• Gas is produced as the sugar turns black

• The sugar becomes a liquid as it melts

Tags

NGSS.MS-PS1-2

The teacher is demonstrating physical and chemical changes to her students. She mixes milk with vinegar and a white, chunky, solid substance is formed.

Which of the following best explains what has occurred?

• A physical change has occurred because the state of matter has changed.

• A chemical change has occurred because a gas was formed.

• A chemical change has occurred because a precipitate was formed.

• A physical change has occurred because the color of the liquid changed.

Tags

NGSS.MS-PS1-2

Which of the following best describes why water is the universal solvent?

• Ice is less dense than liquid water

• Water has strong hydrogen bonds

• Multiple compounds are water soluble

• Water has a high specific heat

In the image, which of the following will be the solute?

• The water in the glass

• The solution once mixed containing both sugar and water

• The glass that holds the final mixture

• The sugar on the spoon

Tags

NGSS.MS-PS1-2

Which of the following statements is true about how using smaller salt crystals would affect the rate of making a salt solution in water?

• Smaller crystals increase the surface area and slow down the dissolving process

• Smaller crystals decrease the surface area and speed up the dissolving process

• Smaller crystals increase the surface area and speed up the dissolving process

• Smaller crystals decrease the surface area and slow down the dissolving process.

Which of the choices below best represents the temperature of a liquid and sample of sugar that would dissolve the quickest?

• Liquid 1:

  36 degrees

  Sugar sample:

  Sugar Cubes

• Liquid 2:

  43 degrees

  Sugar Sample:

  Packet of Sugar

• Liquid 3:

  137 degrees

  Sugar Sample:

  Sugar Cubes

• Liquid 4:

  152 degrees

  Sugar Sample:

  Packet of Sugar

Tags

NGSS.MS-PS1-4

NGSS.MS-PS3-4