Chemical and Physical Changes

A change in which one or more substances are converted into new substances is a _______.

• physical change

• nuclear reaction

• chemical change

• chemical fusion

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

Sam wants to paint her room. She mixed paint with 70% pink and 30% blue in order to get the shade of purple that she wants. Which of the following best describes what occurs when she mixed the paint?

• An energy change occurs as the paint's chemical properties change.

• A phase change occurs, allowing the two colors to mix evenly.

• A chemical change occurs as the different color particles react with each other.

• A physical change occurs, since only the physical properties of paint change.

Which of the following best describes how chemical changes differ from physical changes?

• Physical changes produce no new substances and chemical changes do.

• Physical changes always involve the formation of a gas while chemical changes may not.

• Physical changes can occur inside or outside the substance; chemical changes alwasy occur outside.

• Physical changes involve a change of state; chemical changes involve a change of shape.

Sally is performing an experiment in science class. She mixed two liquids in a test tube. Gas bubbles appeared at the surface of the test tube. What type of changes are most likely taking place?

• Physical change because you can separate the mixture.

• Physical change because it is still a liquid.

• Chemical change because he used chemicals.

• Chemical change because a gas formed.

Tags

NGSS.MS-PS1-2

Over Thanksgiving break, I combined ingredients to make a cake. I mixed butter, sugar, and milk to make the icing. What type of changes created the cake and the icing?

• Both the icing and the cake are formed by physical changes.

• The icing is formed by a chemical change, the cake is formed by a physical change.

• The cake is formed by a chemical change, the icing is formed by a physical change.

• Both the icing and the cake are formed by chemical changes.

Tags

NGSS.MS-PS1-4

Carbon and Oxygen react to form Carbon Dioxide. What are the reactants?

• Carbon and Dioxide

• Oxygen and Carbon

• Oxygen and Dioxide

• CO2

Tags

NGSS.MS-PS1-2

When 16 grams of Tin and Hydrogen Fluoride react, they must produce how many grams of product?

• 32

• 8

• 20

• 16

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

How can the law of conservation of mass apply to a burning log, if all that remains of it is ash?

• The ash has the same mass as the log, although a large percentage of it blows away.

• The law of conservation of mass applies to changes of state but not to chemical reactions.

• The law of conservation of mass applies to substitution and displacement reactions, but not to combustion reactions.

• The masses of the gases and water vapor released into the air by the reaction, plus the ash, equal the mass of the log before burning.

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

Three examples of physical changes are ...

• boiling of water, bursting of a balloon, and crumpling a piece of paper.

• burning of gasoline, rotting of an egg, and exploding fireworks.

• freezing of water, evaporation of gasoline, and rusting of a nail.

• sawing of wood, crushing a can, and toasting a marshmallow.

Which of the following statements best describes the basic structure of an atom?

• Electrons and protons are in motion around a nucleus that contains neutrons.

• Neutrons are in motion around a nucleus that contains protons and electrons.

• Protons are in motion around a nucleus that contains electrons and neutrons.

• Electrons are in motion around a nucleus that contains protons and neutrons.

Tags

NGSS.MS-PS1-1