B) A chemical change because the nail reacts with water/oxygen to create rust (a type of oxide)
To fully understand the problem, we use the ICE table to identify the concentration of the species. We calculate as follows:
Ka = 2.0 x 10^-9 = [H+][OBr-] / [HOBr]
HOBr = 0.50 M
KOBr = 0.30 M = OBr-
<span> HOBr + H2O <-> H+ + OBr- </span>
<span>I 0.50 - 0 0.30 </span>
<span>C -x x x
</span>---------------------------------------------
<span>E(0.50-x) x (0.30+x) </span>
<span>Assuming that the value of x is small as compared to 0.30 and 0.50 </span>
<span>Ka = 2.0 x 10^-9 = x (0.30) / 0.50) </span>
<span>x = 3.33 x 10^-9 = H+</span>
pH = 8.48
<span>Add any other </span>liquid<span> flavorings you might want. Put on your gloves and goggles. Pour a small amount of </span>liquid nitrogen<span> directly into the bowl with the </span>ice cream<span> ingredients. Continue to stir the </span>ice cream<span>, while slowly adding more </span>liquid nitrogen<span>.</span>
Burette is a very accurate measuring instrument when adding solutions and has a measurement error of 0.05 mL.
Small volumes of solutions can be transferred from the burette at a controllable rate.
In this instance NaOH is in the burette.
Initial reading of NaOH is 0.20 mL
end point is the point at which the chemical reaction reaches completion. In acid base reactions, end point is when all the H⁺ ions have reacted with OH⁻ ions.
final reading of NaOH is 24.10 mL
to find the volume of NaOH dispensed we have to find the difference between final reading and initial reading
volume of NaOH added = 24.10 mL - 0.20 mL = 23.90 mL
volume of NaOH dispensed is 23.90 mL
The statement that describes what makes a base weak is that the base will be unable to dissociate completely in water.
<h3>What is a base?</h3>
A base is any of a class of generally water-soluble compounds, having bitter taste, that turn red litmus blue, and react with acids to form salts.
Bases usually dissociate into hydroxide ions (OH-) when in an aqueous solution.
However, a base is termed weak or strong depending on it's ability to dissociate completely. A weak base does not dissociate completely into hydroxide ions when in an aqueous solution.
Learn more about bases at: brainly.com/question/23687757
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