Exothermic is a chemical reaction in which heat is released. Lighting a candle is an example of an exothermic because the flame is the heat being released.
<span> 52.0ml of 0.35M CH3COOH : 0.052 L(0.35M) = .0182 mol of CH3COOH.
</span>
<span>31.0ml of 0.40M NaOH : .031 L(0.40M) = .0124 mol of NaOH.
</span>
<span>After the reaction, .0124 Mol CH3COO- is generated and .058 mol CH3COOH is left un-reacted. The concentration would be 12.4/V and 5.8/V, respectively. Therefore:
</span>
<span>pH = -log([H+]) = -log(Ka*[CH3COOH]/[CH3COO-]) </span>
<span>= -log(1.8x10^-5*5.8/12.4) = 5.07</span>
The experiment is related to the demonstration using Pepper. When pepper is spread over water, it clumps together This is because pepper is hydrophobic. When repeated with sugar and salt, they instantly dissolved. This means they are attracted to water. When also sprinkled on the surface of the water, it floats. This is caused by surface tension.
To break the surface tension of water, one can use aeration or the use of chemicals such as soap molecules which contain a long chain of hydrogen as well as carbon atoms.
<h3>What is surface tension?</h3>
Surface tension is the propensity of liquid surfaces at rest to shrink to the smallest feasible surface area. Surface tension permits items with a higher density than water, such as razor blades and insects (such as water striders), to float on the water's surface without being immersed.
A force tensiometer can be used to measure surface tension. The forces exerted on a probe situated at the liquid-gas or liquid-liquid interface are measured by these devices.
Learn more about Surface Tension:
brainly.com/question/11348644?
#SPJ1
I believe it's the second option. 2 or more elements joined together such that the elements have lost their individual identity in favour of a new set of properties.
The molecule that could diffuse across the plasma membrane is methane (CH4).
<h3>What is diffusion?</h3>
Diffusion is the movement of fluids or substances from regions of high concentration toward regions of lower concentration.
The plasma membrane is the semipermeable membrane that surrounds the cytoplasm of a cell. The semipermeability means that it allows some molecules through but blocks other substances.
The semipermeable plasma membrane readily allows the passage of small hydrophobic and polar molecules.
Therefore, the molecule that could diffuse across the plasma membrane is methane (CH4).
Learn more about semipermeability at: brainly.com/question/1652796
#SPJ1