Can I Make New Stuff Out of Old Stuff? IQWST 7 Grade Unit 1 Test

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

• mixing lemonade powder with water

• burning marshmallows over a fire

• boiling water on a stove

Tags

NGSS.MS-PS1-2

A chemical reaction occurs when substances interact and their atoms _____.

• disappear.

• become new atoms.

• rearrange.

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NGSS.MS-PS1-2

NGSS.MS-PS1-5

A student finds two green powders that look the same. He wants to figure out if the two powders are the same or different substances. Which of the following is the best method to use?

• Combine both green powders and see if there is a chemical reaction.

• Mix the two green powders together and then test the properties.

• Determine the density, solubility, and melting point of each powder and compare.

Tags

NGSS.MS-PS1-2

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

What does this diagram best represent?

• substance

• mixture

Tags

NGSS.MS-PS1-1

If a cup of water is sealed and kept at a constant temperature, then what is true about the motion of the water molecules?

• The molecules keep moving at the same average speed.

• The molecules slow down and eventually stop moving.

• The molecules are not moving if the cup is sitting still.

Tags

NGSS.MS-PS1-4

Which of the following is always true when a substance undergoes a phase change?

• The substance becomes a liquid as it heats up.

• The melting point of the substance changes.

• The substance is made up of the same type of molecules.

Tags

NGSS.MS-PS1-4

NGSS.MS-PS3-4

Which statement is always true about conservation of mass?

• The total mass of the reactants is equal to the total mass of the products.

• The total mass of a system changes in a chemical reaction.

• The mass changes in a phase change, but not in a chemical reaction.

Tags

NGSS.MS-PS1-5

A student measures the masses of two liquids.

One liquid is 14 grams and the other liquid is 18 grams.

Then the student pours both liquids into an open beaker and observes the liquid bubble for a few minutes.

When she measures the mass of the liquid in the beaker it has a mass of 29 grams.

This could be because molecules __________.

• got smaller.

• escaped from the beaker.

• were destroyed.

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

Water (H₂O) cannot be turned into salt (NaCl) through a chemical reaction because ___.

• salt is a mixture of atoms.

• salt and water are made of different atoms.

• water contains liquid atoms and salt contains solid atoms.

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-1