Answer:
B) 5
Explanation:
When an atom lose are gain the electron ions are formed.
There are two types of ions. Cation and anion.
Cation:
It is formed when an atom lose the electrons.
X → X⁺ + e⁻
Anion:
It is formed when an atom gain the electron.
X + e⁻ → X⁻
An atom consist of electron, protons and neutrons. Protons and neutrons are present with in nucleus while the electrons are present out side the nucleus.
All these three subatomic particles construct an atom. A neutral atom have equal number of proton and electron. In other words we can say that negative and positive charges are equal in magnitude and cancel the each other.
if an atom has 8 protons it means there were eight electrons present. when it lost three electron it have +3 charge and number of electron that remain are five. 8-3 = 5
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:
Explanation:
= 0.64 kJ/mol = 640 J/mol
R = 8.314 J/mol.K
Using Van't Hoff Equation:
Answer:
The answer to your question is: 5 friends
Explanation:
Data
Larry bought 12 1/2 pounds of candy
gave each friend 2 1/2 pounds
number of friends = ?
Process
Convert mixed fractions into improper fractions
12 1/2 = (24 + 1) / 2 = 25 /2
2 1/2 = (4 + 1) / 2 = 5/2
Divide the fractions
= 
= 5
Larry gave candies to 5 of his friends
