SSA Review Chemistry

Krystal is exploring the properties of iron. She takes a large iron nail and finds that the nail does not attract other metal objects. Next, she uses a battery and copper wire to transform the nail into an electromagnet. When she connects the circuit, the nail becomes magnetic and can pick up small metal objects like paper clips. This is shown in the illustration below.

What best describes what has happened to the iron in the nail that causes it to become magnetic?

• A physical change has occurred, because the chemical properties of iron remain the same.

• A physical change has occurred, because the chemical attraction between the iron and paper clips.

• A chemical change has occurred, because there is a chemical attraction between the iron and paperclips

• A chemical change has occurred, because the chemical energy in the battery is transformed into magnetic energy in the iron.

Tags

NGSS.MS-PS1-2

The students in Ms. Ramirez's science class are classifying different types of reactions. They have divided the reactions into two columns as shown below. Use the table to answer

the questions that follow. Why are the reactions listed in Column A classified as chemical reactions?

• They form new substances

• They do not change the characteristics of the original substance

• They change the shape of the substance

• The products of the reaction can be changed back into the original products easily

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

Carbon dioxide (CO2) is a substance that is a gas at room temperature. At temperatures below 78°C, carbon dioxide

condenses into a white solid known as dry ice. At normal atmospheric pressures, dry ice changes directly from a solid to a gas without passing through a liquid

phase when its temperature increases. This process is called sublimation. Which of the following best describes the process of sublimation?

• It is a chemical reaction because the kinetic energy of the molecules is changing

• It is a physical reaction because it is a change of state

• It is a physical reaction because the density of the material increases.

• It is a chemical reaction because a new form of carbon dioxide is created

Tags

NGSS.MS-PS1-4

NGSS.MS-PS3-4

Coal contains carbon and other elements. Carbon dioxide forms when coal burns in the presence of oxygen. Which of these is the best evidence that a chemical reaction occurs when coal burns?

• The shape of the coal changes.

• Oxygen is present

• A new substance is produced

• Coal is made up of more than one element.

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

Mathews family has a compost heap in their backyard that recycles yard and food waste into useable soil. During which season would the decomposition happen the fastest?

• Spring

• Summer

• Fall

• Winter

For a laboratory investigation some students put a strip of shiny metal into a beaker of blue solution and then stored the beaker on the shelf overnight. The next morning, the students recorded observations about the metal and the solutions in the box below. Based on their observations, can the students correctly concluded that a chemical reaction occurred?

• No, because the metal strip is still visible.

• Yes, because a new material of a different color formed on part of the metal strip.

• No, because the solution stayed blue.

• Yes, because the volume of the blue solution stayed the same.

Tags

NGSS.MS-PS1-2

A silver ring reacts with compounds containing sulfur in the air to form silver sulfide, a black substance that makes tarnish on the surface of silver objects. To remove the tarnish from the ring, students placed it in a pan lined with aluminum foil and added hot water. Baking soda was added to the hot water and stirred. Students made observations about the process.

Which observation about the process provides evidence of a chemical reaction?

• Hot water heated the aluminum foil

• The liquid solution changed color

• The pan was lined with aluminum foil

• The hot water cooled

Tags

NGSS.MS-PS1-2

As part of an investigation, students combined substances in a beaker to observe chemical reactions. They performed two procedures. They measured the mass of each substance before and after each reaction. The table shows their observations. Assuming the students did not make careless errors, what likely explains these changes in mass?

• 1: All reacts were liquids that evaporated

  2: A gas was formed as one product and it escaped into air

• 1: One of the reactants was converted to thermal energy

  2: All the products were liquids

• 1: The reactants were liquids with different densities

  2: The reactants were combined into only one product

• 1: One of the products was a gas that escaped into the air

  2: A gas from the air reacted with one of the other reactants.

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

A student obtains two strips of magnesium, Mg, ribbon that are each 3 cm long. One strip is placed in a test tube containing 5 ml of water and one in a test tube containing 5 ml of hydrochloric acid. Both liquids are at room temperature. The student’s observations are recorded in the table. Which is NOT supported by the students observations?

• A chemical reaction takes place between magnesium and hydrochloric acid.

• A gas is released in Test Tube 2.

• The substance in both test tubes are reactive only at high temperatures

• Energy is released in the reaction involving hydrochloric 

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5