Answer: Option (d) is the correct answer.
Explanation:
Since the given formula is
. According to cross method formula, magnesium has +2 charge so,
is multiplied by 2.
Thus, 1 molecule of magnesium phosphate will contain 2 atoms of phosphorus.
Therefore, three molecules of magnesium phosphate contains following number of atoms.
Hence, we can conclude that there are 6 atoms of phosphorus in three molecules of magnesium phosphate,
.
Answer:
pH = 3.3
Explanation:
Buffer solutions minimize changes in pH when quantities of acid or base are added into the mix. The typical buffer composition is a weak electrolyte (wk acid or weak base) plus the salt of the weak electrolyte. On addition of acid or base to the buffer solution, the solution chemistry functions to remove the acid or base by reacting with the components of the buffer to shift the equilibrium of the weak electrolyte left or right to remove the excess hydronium ions or hydroxide ions is a way that results in very little change in pH of the system. One should note that buffer solutions do not prevent changes in pH but minimize changes in pH. If enough acid or base is added the buffer chemistry can be destroyed.
In this problem, the weak electrolyte is HNO₂(aq) and the salt is KNO₂(aq). In equation, the buffer solution is 0.55M HNO₂ ⇄ H⁺ + 0.75M KNO₂⁻ . The potassium ion is a spectator ion and does not enter into determination of the pH of the solution. The object is to determine the hydronium ion concentration (H⁺) and apply to the expression pH = -log[H⁺].
Solution using the I.C.E. table:
HNO₂ ⇄ H⁺ + KNO₂⁻
C(i) 0.55M 0M 0.75M
ΔC -x +x +x
C(eq) 0.55M - x x 0.75M + x b/c [HNO₂] / Ka > 100, the x can be
dropped giving ...
≅0.55M x ≅0.75M
Ka = [H⁺][NO₂⁻]/[HNO₂] => [H⁺] = Ka · [HNO₂]/[NO₂⁻]
=> [H⁺] = 6.80x010⁻⁴(0.55) / (0.75) = 4.99 x 10⁻⁴M
pH = -log[H⁺] = -log(4.99 x 10⁻⁴) -(-3.3) = 3.3
Solution using the Henderson-Hasselbalch Equation:
pH = pKa + log[Base]/[Acid] = -log(Ka) + log[Base]/[Acid]
= -log(6.8 x 10⁻⁴) + log[(0.75M)/(0.55M)]
= -(-3.17) + 0.14 = 3.17 + 0.14 = 3.31 ≅ 3.3
Answer:
It's better to explain it.
Explanation:
Neutrons do not affect the electron configuration, but the sum of atomic number and the number of neutrons, or neutron number, is the mass of the nucleus. You know that neutrons are found in the nucleus of an atom. Under normal conditions, protons and neutrons stick together in the nucleus. During radioactive decay, they may be knocked out of there. Neutron numbers are able to change the mass of atoms, because they weigh about as much as a proton and electron together. if your asking What is the role of a neutron in an atom? then, Neutrons are very important in providing stability for an atom. Some atoms don't "need" neutrons - The hydrogen atom does not have any neutrons. However, as the atomic number ( # of protons ) increases, the number of neutrons increases as well.
Protons don't like each other. Naturally, 'positive charges repel', so it wouldn't be possible to have more than one proton in the nucleus. Here's where the neutron comes in.
Hope this helps. :)
Answer:
A solvent is a substance which dissolves a solute. When a solvent dissolves into a solute, it creates a solution
Explanation:
your answer is Kelvin because it is the SI unit of temperature