an ice cube that melts in a glass of lemonade.
the screws on a boat become rusty when sitting in lake michigan
sugar dissolved in hot tea
2006-12-20 14:16:59 · 3 answers · asked by martin 1 in Science & Mathematics ➔ Chemistry
ice melting in physical because you can always freeze it again.
screws rusting is chemical because you cannot change them back into iron screws.
sugar dissolving is physical because you can evaporate the tea and get the sugar back.
2006-12-20 14:21:33 · answer #1 · answered by physandchemteach 7 · 1⤊ 0⤋
An ice cube melting is a physical change. There is no new substance being produced, the water is only changing phase.
Screws rusting is a chemical change. The iron in the screws is reacting with oxygen to make iron oxide, commonly known as rust. This is a new substance.
The sugar dissolving is a physical change. The sugar particles are being broken into smaller and smaller bits of sugar, until they can't be seen and are evenly dispersed in the tea.
2006-12-20 22:23:25 · answer #2 · answered by Erin M 3 · 1⤊ 0⤋
an ice cube that melts in a glass of lemonade. ---Physical change
the screws on a boat become rusty when sitting in lake michigan----chemical change
sugar dissolved in hot tea------physical change
A chemical change is a change that occurs upon a substance that changes one or more of its chemical properties. A chemical change can also occur upon the mixing or combining of two different chemicals. When this happens, we call it a Chemical reaction. Ex...The iron on the boat became iron oxide..
physical change is a change that occurs upon a chemical or upon combining one or more chemicals. A physical change DOES NOT CREATE A NEW SUBSTANCE, it simply changes the form we see the chemical(s) in. Ex. the ice cube jusr melts but its still made out of water and the sugar that is dissolved.
2006-12-20 22:24:13 · answer #3 · answered by coldflesh 3 · 0⤊ 0⤋