Answer : The name of positive ion present in this sample is, hydronium ion.
Explanation :
For formation of a neutral ionic compound, the charges on cation and anion must be balanced.
The cation is formed by loss of electrons by metals and anions are formed by gain of electrons by non metals.
Ion : An ion is formed when an atom looses or gains electron.
When an atom looses electrons, it will form a positive ion known as cation.
When an atom gains electrons, it will form a negative ion known as anion.
As per question, hydronium ion or hydrogen ion is having an oxidation state of +1 called as 
or 
cation and nitrate ion 
is an anion with oxidation state of -1.
Thus they combine and their oxidation states are exchanged and written in simplest whole number ratios to give neutral 
.
Hence, the name of positive ion present in this sample is, hydronium ion.
Answer: I did the research myself since I couldn’t find the answers.
Physical change:
Wax melting from applied heat
Grinding wheat to make flour
Adding copper with gold to make jewelry
Chemical Reaction:
Growth of a seed into a seedling
Making caramel by burning sugar
Tarnishing of silver
Explanation:
Thanks google
Explanation:
A metal atom loses electrons and becomes a positive ion.
The reserve of a fossil fuel might be increased if mining or extraction techniques improve so that more of fuel can be extracted for a profit
Answer:Hence, the bond length in HCl is 125 pm.
Explanation:
Bond length : It is an average distance between the nuclei of two bonded atoms in a molecule.
Also given that bond length is the distance between the centers of two bonded atoms. on the potential energy curve, the bond length is the inter-nuclear distance between the two atoms when the potential energy of the system reaches its lowest value. Beyond this if atoms come closer to each other then their will be repulsion between them.
So, the bond length between the Hydrogen and Chlorine atom in HCl molecule is :
Hence, the bond length in HCl is 125 pm.
