Chemical vs. Physical Changes

The formation of a solid during a  

• Combustion

• Phase Change

• Physical Change

• Precipitate

Another name for a state of matter change such as solid becoming a liquid

• Combustion

• Phase Change

• Physical Change

• Precipitate

• Chemical Reaction

Tags

NGSS.MS-PS1-4

When two or more molecules interact and change into a new susbtance

• Combustion

• Phase Change

• Physical Change

• Precipitate

• Chemical Reaction

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

A chemical reaction involving oxygen that usually gives of heat and/ or light

• Combustion

• Phase Change

• Physical change

• Precipitate

• Chemical Reaction

Tags

NGSS.MS-PS1-5

A change in form or appearance of a substance that does not result in a new substance.

• Combustion

• Phase Change

• Physical Change

• Precipitate

• Chemical Reaction

Mike and Bodhi decide to bake a cake. They gathered their ingredients and supplies.   The first step was to whip the egg whites until fluffy. They melted the butter and set it aside. Next, they chopped some pecans to add to their cake. They began to mix all the other ingredients together including the melted butter. They poured the liquid-like mixture into a pan, spread it out evenly, then baked it at 350⁰ for 30 minutes. Once done, the top of the cake was golden brown. Bodhi was surprised the cake had turned from a light-yellow batter to a darker brown color when finished.

Which of the following is an example of a chemical change occurring? Choose TWO correct answers

• Whipping the egg until fluffy

• Melting the butter

• Baking the cake at a high temperature

• Chopping the pecans

• The golden-brown color of the top of the cake

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

Mike and Bodhi decide to bake a cake. They gathered their ingredients and supplies.   The first step was to whip the egg whites until fluffy. They melted the butter and set it aside. Next, they chopped some pecans to add to their cake. They began to mix all the other ingredients together including the melted butter. They poured the liquid-like mixture into a pan, spread it out evenly, then baked it at 350⁰ for 30 minutes. Once done, the top of the cake was golden brown. Bodhi was surprised the cake had turned from a light-yellow batter to a darker brown color when finished.

Which of the following is evidence of a chemical reaction occurring during this activity? Choose TWO correct answers

• The mixed ingredients changed to a new substancce when baked.

• The butter cchanged from a solid to a liquid.

• The texture of the eggs changed from a gel-like substance to a fluffy substance.

• The top of the cake changed to a new color.

• The shape of the pecans changed after they were chopped.

Tags

NGSS.MS-PS1-2

Mike and Bodhi decide to bake a cake. They gathered their ingredients and supplies.   The first step was to whip the egg whites until fluffy. They melted the butter and set it aside. Next, they chopped some pecans to add to their cake. They began to mix all the other ingredients together including the melted butter. They poured the liquid-like mixture into a pan, spread it out evenly, then baked it at 350⁰ for 30 minutes. Once done, the top of the cake was golden brown. Bodhi was surprised the cake had turned from a light-yellow batter to a darker brown color when finished.

Which of the following is an example of a physical change occurring? Choose THREE correct answers

• Heating the over 350 degrees

• Chopping the pecans

• Melting the butter

• Baking the cake at a high temperature

• Gathering all the ingredients and supplies

Short Answer: Respond to each item with complete sentences.

During a lab investigation, students followed this procedure:

1.Measure the mass of the baking soda.

2.Place the baking soda in a small beaker or glass container

3.Using the graduated cylinder, measure 50 mL of vinegar.

4.Add 3 drops of liquid dish soap to the graduated cylinder.

5.Slowly pour the vinegar mixture into the beaker containing the baking soda.

6.Record your observations.

Students observed that the baking soda fizzed, and the liquid expanded to overflow the beaker. After the bubbles stopped, students observed there was very little baking soda left in the bottom of the beaker.

QUESTION: What kind of change occurred? Support your answer using evidence and reasoning.

• A chemical change occurred. A chemical change occurring is evident when the vinegar was poured into the baking soda mixture, and bubles or fizzing appeared. When fizzing was done, there was little baking soda left in the beaker.

• A physical change. A physical change occurring is evident when the vinegar was poured into the baking soda mixture, and bubles or fizzing appeared. When fizzing was done, there was little baking soda left in the beaker.

Answer explanation

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

Short Answer: Respond to each item with complete sentences.

QUESTION: What type of change occurs when you dissolve sugar in water? Use scientific reasoning to support your answer.

• Chemical change: A chemical change occurs. When sugar is mixed with water, the sugar dissolves in the water, but no new substances are created. If the water evaporates, the water changes state of matter from liquid to gas, yet the sugar remains unchanged.

• Physical change: A physical change occurs. When sugar is mixed with water, the sugar dissolves in the water, but no new substances are created. If the water evaporates, the water changes state of matter from liquid to gas, yet the sugar remains unchanged.