Answer:
[Na⁺] = 1.99 M
Explanation:
Na₂S is a ionic salt that can be dissociated.
Dissociation equation is:
Na₂S → 2Na⁺ + S⁻²
1 mol of sodium sulfide can give 2 moles of sodium cation.
We convert moles of salt: 78 g . 1mol / 78.06 g = 0.999 moles
As ratio is 1:2, after dissociation we have (0.999 . 2) = 1.998 moles of Na⁺
Molarity is a type of concentration.
It indicates moles of solute in 1 L of solution and in this case, we have 1 L as final voulme.
Moles of Na⁺ are 1.998 moles. Then molarity (mol/L) is:
M =1.99 mol/L
Answer:
99•g
Explanation:
Well, ONE mole of water has a mass of 18.01⋅g⋅mol−1. and 5.5⋅mol has a mass of approx. <u>99⋅g.</u>
Since the half-life is 4.5 billion years, two half-lives would have elapsed after 9 billion years.
<span>If you start with 400 g, half decays during the first half-life, leaving 200 g. </span>
<span>During the second half-life, half of the 200 g decays, leaving 100 g.</span>
Answer:
Explanation:
Arrhenius theory:-
The Arrhenius theory was introduced introduced by Swedish scientist named Svante Arrhenius in 1887.
According to the theory, acids are the substances which dissociate in the aqueous medium to produce electrically charged atoms ( may be molecule). Out of these species furnished, one must be a proton or the hydrogen ion, 
.
So,
The expression for acid, 
is:-
Answer:
Carbon has an atomic number of 6. That means a carbon atom has 6 protons, 6 neutrons, and 6 electrons.
