Select the items that describe a chemical property below. Choose THREE correct answers.
1:Heated iron can be hammered into a sword.

2:A handwarmer gets warm when it is opened and exposed to air.

3:Propane ignites to heat a grill.

4:Cotton is dyed red to make a dress.

5:A cylinder in an engine uses gasoline to move pistons.

6:Maple syrup is thicker than water.​