Science Next Generation Standards

While working on an activity to investigate physical and chemical reactions, a student mixes two clear liquids in a beaker.  When the two clear liquids mix, the result is a mixture that contains a clear liquid and an orange solid precipitate.

• The resulting chemical turned a different color than the initial chemicals.

• A precipitate formed. 

• The resulting chemical changed size

• The resulting chemical has changed shapes.

• The resulting chemical changed temperature. 

Tags

NGSS.MS-PS1-2

Throughout the day, you use plastics. Even if you and your family take cloth bags to the grocery store to replace the plastic bags given out, your day is filled with plastics. Are you reading this on a computer? Plastic. Are you drinking a bottle of soda or juice? Plastic. Did you get to school in a car? Plastics throughout!

What are plastics? Where do they come from? Plastics are derived from materials found in nature, such as natural gas, oil, coal, minerals, and plants. The very first plastic-like material, rubber, comes from the rubber tree. Today the plastics we use are synthesized in a lab or factory. Interest in making plastics arose in the 1800s to replace natural materials that were becoming scarce or hard to find such as ivory and tortoiseshell. The first synthetic plastics were derived from cellulose, a substance found in plants. Cellulose was heated with various chemicals and this resulted in a new material that was extremely durable and flexible. The raw materials for today’s plastics come from the hydrocarbons that are found in already depleting resources like natural gas, oil, and coal. Plastics are polymers or chains of molecules linked together and these chains are composed of various elements. Recycling plastic is notoriously difficult. Only 9% of all plastic ever made has been recycled into new plastics.

Plastics are everywhere in our lives. Yet some people are opposed to plastic manufacture and use. Based on the information in the prompt, cite one reason why some people are worried about the continued widespread use of plastics.

• Plastics that become litter can harm wildlife in various habitats.

• Many plastics cannot be recycled and remain in the environment forever.

• Producing plastics depletes our already dwindling supply of fossil fuels.

• The synthesis of plastics produces pollutants, especially greenhouse gases.

Tags

NGSS.MS-ESS3-3

NGSS.MS-PS1-3

How many valence electrons does this element have?

• 1

• 2

• 3

• 4

• 5

Tags

NGSS.MS-PS1-1

A chemical change occurs when...

• the identity of a substance changes but its appearance does not.

• neither the appearance of a substance nor its identity changes.

• both the physical properties of a substance and its identity change.

• 
  the appearance of a substance changes but its identity does not.

Tags

NGSS.MS-PS1-2

A piece of metal has a mass of 60 g and a volume of 3 cm^3, what is the density of the metal?

Hint: # Density = mass/volume 

• 4g

• 20g/cm^3

• 10g/ml

• 20g

​Water is boiled and steam is produced. This is a physical change because the water particles....

• have turned into something new.

• are still water particles.

• have reacted with each other.

• have been destroyed.

Tags

NGSS.MS-PS1-4

Select all of the following events in which a chemical change occurs.

• 
  Chocolate syrup dissolves into warm milk. 

• Toast is lightly charred in a toaster.

• A piece of paper is cut up into 12 pieces.

• Two unknown liquids are mixed together and a gas is produced.

• Sugar is heated until it turns into a brown caramel sauce.

Tags

NGSS.MS-PS1-2

​Which of these represents a chemical change? 

• A match is lit, creating a yellow-orange flame.

• 
  A small piece of ice melts, changing from a solid to a liquid.

• A ball of clay sinks in water, and floats when reshaped.

• A pot of water is heated to boiling, and evaporation occurs.

Tags

NGSS.MS-PS1-2

Which of these is an example of a physical change?

• Melting ice

• Rusting metal

• Baking a cake

• Burning leaves

Tags

NGSS.MS-PS1-4

Cation - a positively charged ion, i.e. one that would be attracted to the cathode in electrolysis.

If this element were to become a cation, which of the following would be true?

• The atom would gain an electron

• The atom would lose an electron

• The atom would gain a proton

• The atom would lose a proton

Tags

NGSS.MS-PS1-1