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
The mixture contains:
CaCO3 + (NH4)2CO3 in which the amount of carbonate CO3 = 60.7% by mass
Let, the total mass = 100 grams
Mass of CaCO3 = x grams
Mass of (NH4)2CO3 = y grams
Thus, x + y = 100 ------------(1)
Mass of CO3 = 60.7% = 60.7 g
Molar mass of CO3 = 60 g/mol
Total # moles of CO3 = 60.7 g/60 g.mol-1 = 1.012 moles
The total moles of CO3 comes from CaCO3 and (NH4)2CO3. Therefore,
moles CaCO3 + moles (NH4)2CO3 = 1.012
mass CaCO3/molar mass CaCO3 + mass (NH4)2 CO3/molar mass = 1.012
x/100 + y/96 = 1.012---------(2)
based on equation 1 we can write: y = 100-x
x/100 + (100-x)/96 = 1.012
x = 71.2 g
Mass of CaCO3 = 71.2 g
Answer:
This question is incomplete, the complete part of the question is as follows:
This best demonstrates which type of an interaction between the plants?
A. cooperation
B. parasitism
C. commensalism
D. competition
The answer is D
Explanation:
Organisms in their natural environment interact with one another in so many ways. The ways by which this interaction occurs are; competition, predation, commensalism etc.
Competition is the interaction between two organisms in which one or both organisms are harmed due to limited resources. Competition occurs when the organisms involved occupy the same niche or utilize the same limited resources.
In this question involving corn plants and milkweed plants. They are said to grow in the same area. Over several years, the milkweed plants have taken over the field and the corn plants no longer have space to grow. In this case, there is a limited space for growth, hence, the corn plant and milkweed COMPETE.
Couple examples of protists are Quartan Malaria, Plasmodium Falciparum, and Babesia Canis
Answer:
<u><em>Hope it helped </em></u>↓
Explanation:
Electromagnets are basically coils of wire which behave like bar magnets with a distinct north and south pole when an electrical current passes through the coil. The static magnetic field produced by each individual coil loop is summed with its neighbor with the combined magnetic field concentrated like the single wire loop we looked at in the last tutorial in the center of the coil. The resultant static magnetic field with a north pole at one end and a south pole at the other is uniform and a lot more stronger in the center of the coil than around the exterior. So a good question could be "Are electromagnets a magnet that respells, or attracts?" Then find away to explain that question/
(you don't have to do this question it is just a example.)
