Question

1. fill in the chart: write physical change and chemical change for the following scenarios.

description	physical and chemical change (we will assume all chemical changes are also physical changes)

|condensing water vapor|
|combustion of gasoline|
|turning water into h2 and o2 gas|
|milk souring|
|sublimation of dry ice|
|turning copper into wire|
|fermentation of sugar into alcohol|
|evaporating water|

Explanation:

Step1: Recall physical - change definition

A physical change is a change in the form or state of matter without a change in its chemical composition.

Step2: Recall chemical - change definition

A chemical change results in the formation of new substances with different chemical properties.

Step3: Analyze condensing water vapor

Water vapor changes from gas to liquid. No new substances are formed. So it is a physical change.

Step4: Analyze combustion of gasoline

Gasoline reacts with oxygen to produce carbon - dioxide, water, etc. New substances are formed. So it is a chemical (and physical) change.

Step5: Analyze turning water into H2 and O2 gas

Water decomposes into hydrogen and oxygen gases. New substances are formed. So it is a chemical (and physical) change.

Step6: Analyze milk souring

Microorganisms cause chemical reactions in milk, changing its composition. New substances are formed. So it is a chemical (and physical) change.

Step7: Analyze sublimation of dry ice

Dry ice (solid CO2) changes directly to CO2 gas. No new substances are formed. So it is a physical change.

Step8: Analyze turning copper into wire

The shape of copper changes, but its chemical composition remains the same. So it is a physical change.

Step9: Analyze fermentation of sugar into alcohol

Sugar is converted into alcohol and carbon - dioxide by yeast. New substances are formed. So it is a chemical (and physical) change.

Step10: Analyze evaporating water

Water changes from liquid to gas. No new substances are formed. So it is a physical change.

Answer:

Description	Physical and Chemical Change
Combustion of gasoline	Chemical (and physical) change
Turning water into H2 and O2 gas	Chemical (and physical) change
Milk souring	Chemical (and physical) change
Sublimation of dry ice	Physical change
Turning copper into wire	Physical change
Fermentation of sugar into alcohol	Chemical (and physical) change
Evaporating water	Physical change