<span>We know that protons gives positive charge, neutrons no charge and electrons negative, then +14 - 12 = +2
So the charge of the atom is sign positive and magnitude 2</span>
Answer:
What is mole used for?
Explanation:
The mole is widely used in chemistry as a convenient way to express amounts of reactants and products of chemical reactions.
SI base units: Base unit (Dimensionless)
Symbol: mol
Unit of: Amount of substance
Unit system: SI base unit
Answer:
New pH = 3.84
Explanation:
First of all we may think that if the buffer has pH 3.98 and we're adding H⁺, pH's buffer will be lower, as the [H⁺] is been increased.
Let's determine the moles of each compound:
0.23 M . 1.3L = 0.299 moles of NaBz
0.38 M . 1.3L = 0.494 moles of HBz
We add 0.058 of HCl, which is the same as 0.058 moles of H⁻
HCl → H⁺ + Cl⁻
As we add the moles of protons, these are going to react to the Bz⁻
In the buffer system we have these dissociations:
NaBz → Na⁺ + Bz⁻
HBz → H⁺ + Bz⁻
So, as we add protons, we have a new equilibrium:
Bz⁻ + H⁺ ⇄ HBz
In 0.299 0.058 0.494
Eq 0.241 - 0.552
Protons are substracted to benzoate, so the [HBz] is now higher than before. We calculate the new pH, with the Henderson Hasselbach equation
pH = pKa + log (Bz⁻/HBz)
pH = 4.20 + log (0.241 / 0.552) → 3.84
Answer:
they are single cells that lack a nucleus and tend to live in extreme conditions.- B.
Answer:
The atomic mass of methane (CH4)is 12 amu for the carbon plus 4 x 1 amu for the four hydrogens, for a total of 16 amu. Therefore, the molar mass of methane is 16g.
