-Melting ice is a physical change while creating the compound, water (H2O), is chemical. Why?
Melting ice is considered a physical change because it involves a change in the state of matter from solid to liquid, without altering the chemical composition of the substance. Ice is still composed of water molecules before and after melting.
On the other hand, creating water (H2O) from its elemental components, hydrogen (H2) and oxygen (O2), involves a chemical change. This is because it involves a rearrangement of the atoms in the molecules to form a completely new substance with different chemical properties. The hydrogen and oxygen atoms combine to form new chemical bonds and create water molecules with different properties than the original hydrogen and oxygen gases.
Melting ice is a physical change because it involves a change in the state of matter from solid to liquid, without any change in the chemical composition of the substance. In other words, the water molecules in ice remain the same during the melting process.
Creating the compound water (H2O), on the other hand, is a chemical change because it involves a rearrangement of the atoms in the substances involved. When hydrogen gas (H2) and oxygen gas (O2) react and combine under certain conditions, they chemically bond together to form water (H2O). The individual hydrogen and oxygen atoms combine and form new molecular structures, resulting in a different substance with new chemical properties.
Melting ice is a physical change because it is a process where a substance, in this case, ice, changes its state from solid to liquid. The water molecules in the ice retain their chemical composition and arrangement during the melting process.
On the other hand, the creation of the compound water (H2O) is a chemical change. It involves a chemical reaction where the hydrogen gas (H2) and oxygen gas (O2) combine to form water molecules (H2O). In this reaction, the hydrogen and oxygen atoms rearrange their chemical bonds and form new compounds, resulting in the formation of water. This process is not reversible by simply changing the physical state of water (like melting or freezing).
To understand why melting ice is a physical change and the formation of water is a chemical change, we can look at the definitions of physical and chemical changes:
1. Physical change: A physical change is a change in a substance that does not alter its chemical composition. It involves a change in the physical properties of a substance, such as shape, size, phase, or state, without forming a new substance.
2. Chemical change: A chemical change is a change in a substance that results in the formation of one or more new substances with different chemical properties. It involves a rearrangement of atoms or molecules, breaking and forming new chemical bonds.
By analyzing the processes involved in melting ice and forming water, we can determine that melting ice is a physical change, while creating the compound water involves a chemical change.