Answer:
5.9x10²² atoms of Cu are in one naira coin
Explanation:
To solve this question we need to find the mass of Copper. Then, using its molar mass (Cu = 63.546g/mol) we must find the moles of Cu and its atoms using Avogadro's number:
<em>Mass Cu:</em>
7.3g * 86% = 6.278g is the mass of Cu.
<em>Moles Cu:</em>
6.278g * (1mol / 63.546g) = 0.099moles Cu
<em>Atoms Cu:</em>
0.099moles Cu * (6.022x10²³atoms / 1mol) =
<h3>5.9x10²² atoms of Cu are in one naira coin</h3>
Answer:
The compound you will use is the Dibasic phosphate
Explanation:
Simple phosphate buffer is used ubiquitously in biological experiments, as it can be adapted to a variety of pH levels, including isotonic. This wide range is due to phosphoric acid having 3 dissociation constants, (known in chemistry as a triprotic acid) allowing for formulation of buffers near each of the pH levels of 2.15, 6.86, or 12.32. Phosphate buffer is highly water soluble and has a high buffering capacity,
In this case the most efficient way is to disolve the dibasic compound which in the reaction with the water will form the monobasic phosphate.
To make the buffer you have to prepare the amount of distillate water needed, disolve the dibasic phospate, and then adjust with HCl or NaOH depending on the pH needed.
The answer to both is D. Here's why:
For the first, whenever motion changes in a magnetic field, it causes electrons to move. Electricity, which is needed to power a lightbulb, is just a term for movement of these electrons. Electrons aren't created, they're always there in the wire. It's just that the permanent magnet gets them to move, which produces electricity.
For the second, it is very similar to the first. A magnet won't cause any electric current at rest, it always requires motion in order to produce an electric current. If you keep both of those in mind, it should help in the future. Hope this helps!
Since 1mL=1cm^3 the wood would sink due to it being more dense. I.e. 0.95>0.88