Explanation:
When a metal replaces another metal in solution, we say such a reaction has undergone a single displacement reaction.
In such a reaction, metal higher up in the activity series replaces another one due to their position.
To known the metal or metals that will replace the given copper, we need to reference the activity series of metals.
Every metal higher than copper in the series will displace copper from the solution.
So, there metals are: potassium, sodium, lithium, barium, strontium etc.
You must remember that oxidation number of hydrogen in acids is always +1, oxidation number of oxygen in oxides & acids is always -2... metals has always oxidation number on plus!
group NO3 comes from HNO3...and oxidation number of whole acid group is always on minus and equal to the amount of hydrogen atoms in this acid... so oxidation number of NO3 = -1
we have 2 NO3 groups so 2*(-1) = -2 and that is the reason why oxidation number of Fe in this formula must be +2... because sum of all elements always gives 0!
Now we could count of oxidation number for nitrogen... we write HNO3 and start counting from right to left:
3*(-2) from oxygens + 1 from hydrogen = -5
so nitrogen must have +5 oxidation number... because sum all in formula must be 0.
Answer:
Hydrogen is an element
Explanation:
Hydrogen is an element with only hydrogen atoms, whereas air, carbon dioxide, and water are all made up of multiple elements with different types of atoms.
<u>Answer:</u> The atomic mass of these species is different and atomic number remains same.
<u>Explanation:</u>
Isotopes are the chemical species of the same element having different number of neutrons.
- Atomic number is equal to the number of protons or electrons present in that element.
Atomic Number = Number of electrons = Number of protons
- Atomic mass is defined as the sum of number of protons and neutrons contained in an atom.
Atomic Mass = Number of protons + Number of neutrons
For isotopes, as the number of neutrons differ, the atomic mass also differs.
For Example: Carbon has 3 naturally occurring isotopes: 
. The atomic number remains the same but atomic mass differs.
Hence, for isotopes, the atomic mass of these species is different and atomic number remains same.
