Answer: The oxidation number of Cu decreased
Explanation: In Cu2O equation Cu has an oxidation number of
Cu+1 O-2
then in the product side Cu is represented as a single element.
The rule on oxidation number for an individual element is always O
So Cu has 0 oxidation number.
Vanadium
V 1s²2s²2p⁶3s²3p⁶4s²3d³
As we know methane is an Alkane to separate an Alkane We use fractional distillation to put each liquid into its fraction with the right temperature group
Answer:
A. The object broke apart and seemed to disappear when dropped into the glass of water.
Explanation:
In a physical change, the physical properties of the matter usually the state of the matter is altered. Most physical changes are usually reversible and does not lead to the production of new substances.
When the solid object was dropped into the water beaker and it dissolves by disappearing the solution, we have experienced a physical change. This is a dissolution reaction. If we heat the solution and water given off, we can recover back the dissolved solid object.
Question 22: conclusion
Question 23: analyze