The electron configuration for a atom whose element has a atomic number of 8 (Oxygen) is 2,6
Explanation:
Molarity is defined as the the number of moles present in a solution divided by volume in liters.
Mathematically, Molarity = 
As it is given that number of moles present into the solution are 2.00 moles and volume is 4 liter. Therefore, calculate the molarity of solution as follows.
Molarity =
= 
= 0.5 M
Thus, we can conclude that the concentration of given solution is 0.5 M.
At room temperature:
a. Gold is a solid, as in the gold jewelry that most people have.
b. Gasoline is a liquid, as it is pumped in cars to use as fuel.
c. Oxygen is a gas, as we breathe it in from the atmosphere.
d. Neon is a gas, it is one of the noble gases in the periodic table.
e. Olive oil is a liquid, as it is used in cooking.
f. Sulfur is a solid, and it can be found naturally in mining.
g. Mercury is a liquid which is often seen in thermometers.
Answer:
Second option. 3
Explanation:
In order to balance a equation you need to have the same amount of atoms/moles in both sides.
Na₃PO₄ + _ HCl → 3NaCl + H₃PO₄
In reactant side we have 3 Na and we have the same amount in product side.
We also have 1 P and 4 O in both sides of the equation.
As we have 3 moles of NaCl in product side, this means we have:
NaCl → Na⁺ + Cl⁻
3 moles of Na⁺ and 3 moles of Cl⁻. In conclussion we need 3 moles of Cl⁻ in reactant side.Then, the stoichiometry of HCl must be, 3.
3 moles of HCl means that we have 3 moles of protons (H⁺).
HCl → H⁺ + Cl⁻
If you see the phosphoric acid, we also have 3 moles of protons.
H₃PO₄ → 3H⁺ + PO₄³⁻
Complete balanced equation is:
Na₃PO₄ + 3HCl → 3NaCl + H₃PO₄
