Explanation:
Electrical energy is the energy produced due to flow of electrons.
Whereas a reaction in which oxidation and reduction reaction takes place is known as a redox reaction. Basically, there is exchange of electrons that take place in a redox reaction.
For example,
Oxidation half reaction:
Reduction half reaction:
Hence, this flow of electrons acts as a source of electrical energy.
B) copper
C) methane
D) rust
It is B. I took the test!!
b.The reaction cannot occur because water is a reactant.
c.Copper has a higher activity than hydrogen and cannot replace it.
d.The reaction proceeds too slowly to create products.
The reason why H₂O +Cu does not proceed to a product is that
copper has a lower activity than hydrogen and cannot replace it (answer A)
Explanation
Replacement reaction is type of a reaction in which element react with compound and take place of another element in that compound.
That is the more reactive element replaces the less reactive element from it's compound.
Since H₂ is more reactive than Cu in reactivity series therefore no reaction occur between H₂O +Cu since Cu cannot replace H₂ from its compound.
The symbol :
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): protons, electrons, and neutrons
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