Answer:
phase change always has two phases in contact during the change. melting => solid & liquid; evaporation (boiling) => liquid & vapor. If only one phase is present, then phase change is not occurring. Also, when two phases are in contact, no temperature changes occur. Only the pure phase demonstrates temperature change when measured. Example, when ice is added to water, at thermal equilibrium (temp = 0°C) the water temp will not continue to change. Only when all the ice has melted will the water temperature demonstrate a measured temperature change.
Explanation:
Answer:
have the same number of atoms
Explanation:
Atoms of the same element have the same atomic number so the number of protons (and electrons) are same. But they have same or different mass number (like that for isotopes) . Different mass number will have different number of neutrons.
What is the oxidation number of manganese (Mn) in
potassium permanganate (KMnO4)?
+3
+5
+6
+7
The oxidation number of manganese (Mn) in potassium
permanganate (KMnO4) is +5.
demonstrates the formation of a solid precipitate