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 weighted average atomic mass of Silicon is 28.1
(27.98 x .9223) + (28.98 x .0468) + (29.97 x .0309)
= 25.81 + 1.36 + .93
= 28.1
Answer: Option (c) is the correct answer.
Explanation:
Generally, when we move from top to bottom in a group then there occur increase in the number of electrons due to which there will also occur increase in the number of shells.
As atomic size is the distance between the nucleus and valence shell of an atom. Hence, more is the number of shells present in an atom more will be its atomic radius.
Thus, we can conclude that the statement atomic radius of elements in a group decreases as you go from top to bottom, is generally FALSE.