Physical & Chemical Changes STAAR

Which statement best describes that a chemical reaction occurs as a cake bakes

• the water in the cake evaporates

• the cake rises as gas bubbles form in the cake

• the cake takes the shape of the container it is baked in

• the water in the cake batter is used to keep the cake moist as it bakes

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-4

NGSS.MS-PS1-5

During a lab, students put shiny metal into a beaker of blue solution and left it overnight. The next morning, they observed:

· The solution is lighter in color

· The volume is the same

· The metal in the solution formed dark particles on it

· The dark particles on the metal fall off when touched

· The metal not in the solution is still shiny

WHAT IS THE EVIDENCE THAT A CHEMICAL CHANGE OCCURRED?

• new material of a different color formed on the metal

• the metal strip is still visible

• the volume stayed the same

Tags

NGSS.MS-PS1-2

The sulfur in a silver ring reacts to the air and makes it tarnish or turn black. T remove the tarnished black color, students place it in a pan of hot water and baking soda. Students stir the mixture and observe a chemical reaction. The evidence is...

• the water heated the ring

• the liquid solution changed color

• the pan was made of aluminum

• the hot water cooled

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

A student places one strip of magnesium in test tube 1 with water and another strip in test tube 2 with hydrochloric acid (HCl).

Test Tube 1 (Water):

No activity takes place

Temperature remains constant

The appearance of the metal does not change

Test Tube 2 (HCl):

Bubbling occurs

The temperature increases

The metal strip gets smaller and disappears

WHAT STATEMENT IS NOT OBSERVED BY THE STUDENT?

• a chemical reaction takes place between the magnesium and the HCl

• a gas is released in test tube 2

• the substance in both test tubes are chemical reactions

• a chemical reaction takes place between the magnesium and water

Tags

NGSS.MS-PS1-2

A car releases nitrogen dioxide when it is driven. It can also be produced by natural causes such as forest fires and lightning. The equation for producing nitrogen dioxide is shown in the picture. What is the evidence that a chemical change has occurred?

• a gas is present

• it is produced in nature and in by people

• the state of matter remains the same

• a brown gas is produced

Tags

NGSS.MS-PS1-2

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

A student poured a blue solution of CuSO4 into a beaker. Then placed a shiny, silver-colored strip of zinc metal in the solution and observed the changes. What evidence supports that a chemical change occurred?

• a dark solid formed on the zinc metal

• the zinc metal remained silver-colored and shiny

• the CuSO4 solution turned blue when zinc metal was added

• none of these

Tags

NGSS.MS-PS1-2

What evidence is there that a chemical change occurred?

• a new substance has formed

• a change in state of matter occurred

• a color change has taken place

• fizzing and bubbles formed

Tags

NGSS.MS-PS1-2

In an experiment a red liquid was mixed with a yellow liquid. What evidence shows a chemical change took place?

• the liquid turned orange

• the yellow liquid floated on the red liquid

• the formation of gas

• no change in state of matter

Tags

NGSS.MS-PS1-2

In an experiment the teacher put water in a glass bowl and began to heat it. The water began to bubble after a few minutes. What change is occurring?

• physical change

• chemical change

• a new substance

• dissolving

Tags

NGSS.MS-PS1-4

NGSS.MS-PS3-4

NGSS.MS-PS3-5