Changes in Matter

Anika, Abigail, and Michael are conducting an experiment in their science class. They are trying to understand the main difference between physical and chemical changes. Can you help them?

• Physical changes only affect the chemical properties of a substance, while chemical changes result in the formation of new substances. For example, if Anika melts an ice cube (physical change), it doesn't create a new substance, but if Michael burns a piece of paper (chemical change), it results in ash, a new substance.

• Physical changes and chemical changes both result in the formation of new substances. For instance, if Abigail tears a piece of paper (physical change), or Michael burns a piece of paper (chemical change), both result in new substances.

• Physical changes and chemical changes both only affect the physical properties of a substance. For example, if Anika melts an ice cube (physical change), or Abigail dissolves sugar in water (chemical change), both only change the physical properties of the substances.

• Physical changes only affect the physical properties of a substance, while chemical changes result in the formation of new substances. For instance, if Michael breaks a glass bottle (physical change), it doesn't create a new substance, but if Abigail burns a piece of paper (chemical change), it results in ash, a new substance.

Nora, Grace, and Noah were conducting an experiment in their science class. They observed both physical and chemical changes. According to the law of conservation of mass, what would they notice about the mass of the substances involved in these changes?

• The mass disappears.

• The mass remains constant.

• The mass decreases.

• The mass increases.

Abigail was camping with her friends Arjun and Olivia. They decided to make a bonfire. Which of the following actions of theirs is an example of a chemical change?

• Burning of wood for the bonfire

• Mixing of salt and water for their soup

• Melting of ice for their drinks

• Cutting a piece of paper to make a map

Oliver, Samuel, and James were conducting a science experiment. They observed that when ice melts into water, the chemical composition of the substance remains the same. Is this observation True or False?

• Sometimes

• False

• Not sure

• True

Kai, Noah, and Liam were conducting a chemistry experiment. They were debating whether in a chemical change, the mass of the reactants they used would always be equal to the mass of the products they obtained. Is this statement true or false?

• Not always

• False

• Sometimes

• True

Benjamin, Luna, and Samuel are conducting a chemistry experiment. They are curious about how temperature might influence their experiment. Specifically, how does temperature influence chemical changes in their experiment?

• Temperature only affects the color of the chemicals they are using.

• Temperature influences the rate of reaction and the equilibrium position of the chemical reaction in their experiment.

• Temperature causes the chemical changes in their experiment to reverse.

• Temperature has no effect on the chemical changes in their experiment.

David, Arjun, and Mason are conducting a chemistry experiment. They are debating whether increasing the temperature will always speed up their chemical reaction. Is this statement true or false?

• Sometimes

• It depends

• False

• True

During a science experiment, Samuel, Anika, and Sophia heated a substance. What happened to the particles of the substance when the temperature was increased?

• The particles lost kinetic energy and moved slower, leading to a decrease in the rate of the reaction.

• The particles changed their chemical composition, resulting in a different substance.

• The particles gained kinetic energy and moved faster, leading to an increase in the rate of the reaction.

• The particles became more stable and less reactive, causing the reaction to stop.

During a camping trip, Benjamin, Ava, and William noticed a change in a substance that was influenced by temperature. Which of the following could be an example of such a chemical change?

• Boiling water for their morning coffee

• Melting ice for their drinks

• Burning wood for their campfire

• Mixing salt and water for their soup