Sodium-22 remain : 1.13 g
<h3>Further explanation
</h3>
The atomic nucleus can experience decay into 2 particles or more due to the instability of its atomic nucleus.
Usually, radioactive elements have an unstable atomic nucleus.
General formulas used in decay:

T = duration of decay
t 1/2 = half-life
N₀ = the number of initial radioactive atoms
Nt = the number of radioactive atoms left after decaying during T time
half-life = t 1/2=2.6 years
T=15.6 years
No=72.5 g

Answer:
The atomic number of<span>N<span>157</span></span>
The number of protons is 7
The number of electrons is 7
The number of neutrons is 8
Explanation:
The atomic number of Nitrogen is 7 because Nitrogen has 7 protons.
The seven protons attract 7 electrons in the ground state.
If the atom had fewer or more than 7 protons the atom would not be Nitrogen.
The mass of the atom is the sum of protons and neutron. so
p + n = mass ( protons (p) and neutrons(n) both have an atomic mass of one
7 + n = 15 subtract 7 from both sides
<span>7−7+n=15−7</span>
n = 8
Answer: Nitrogen
Explanation: Nitrogen has an atomic number of 7 and an atomic mass of about 14 u
Answer:
Ni(s) + H₂O(l) -------------> [Ni(H₂O)₆]²⁺
Explanation:
Data Given:
Reactants:
Ni(s) + H₂O(l)
Product = ?
Solution:
Names of the Reactants
Ni = Nickel
H₂O = water
Reaction:
Normally nickel directly does not react with water under normal condition. But indirectly in acidic or neutral condition it form complex ion.
For this it first dissolve slowly in dilute acid, in this reaction it liberate Ni²⁺ ions these nickel ions form light green complex ions in aqueous solution.
Ni(s) + H₂SO₄(aq) -------> Ni²⁺(aq) + SO₄²⁻(aq) + H₂
This is a type of complex formation in which Nickel react with water and produced a light green color new complex ion or product.
Complete reaction is as under
Ni(s) + H₂O(l) -------------> [Ni(H₂O)₆]²⁺
Balance Reaction:
Ni(s) + 6 H₂O(l) -------------> [Ni(H₂O)₆]²⁺
So.
by this reaction one product is formed that is [Ni(H₂O)₆]²⁺ named as hexaqua nickel ion