If copper is heated with iron oxide there is no obvious reaction because
copper is less reactive than iron.
On a reactivity chart, copper is far below iron. This makes it impossible for a replacement reaction to occur, so the equation doesn't change.
I hope I helped!
Buoyancy is considered a physical property. It is a type of physical property because it is related to the density and weight of the item, which are both physical.
Nitrogen accounts for 78% of the atmosphere, oxygen 21% and argon 0.9%. Gases like carbon dioxide, nitrous oxides, methane, and ozone are trace gases that account for about a tenth of one percent of the atmosphere.
The symbol : 
<h3>Further explanation
</h3>
There are two components that accompany an element, the mass number and atomic number
Atoms are composed of 3 types of basic particles (subatomic particles): <em>protons, electrons, and neutrons
</em>
The Atomic Number (Z) indicates the number of protons and electrons in an atom of an element.
Atomic number = number of protons = number of electrons ⇒ neutral number
Atomic mass is the sum of protons and neutrons
Atomic Number (Z) = Atomic mass (A) - Number of Neutrons
The element has 71 electrons and a charge of +1 , so
Number of protons = 71 + 1 = 72
Number of protons = the atomic number = 72
The element with atomic number 72 is Hafnium(Hf)
The atomic mass of Hf = 178 g/mol
Answer:
1. Alkalinity
2. True
3. Red
Explanation:
1. 8-14, which are the bases, are alkaline
2. Salt lowers the melting/freezing point of water
3. Blue --> Red is Acid