Answer:
<u> Translation:</u>
Classify the following elements into metals, nonmetals, metalloids, or gases, noble
: fluorine, sulfur, nitrogen, chlorine, magnesium, helium, sodium, bromine, silicon, tellurium.
- Metals: magnesium and sodium.
- Nonmetals: fluorine, chlorine, bromine, sulfur and nitrogen.
- Metalloids: silicon and tellurium.
- Noble gases: helium.
Explanation:
Metals: They occupy the left and central areas of the Periodic Table; therefore, they constitute a majority group of the elements.
Nonmetals: They are located in the upper right region of the Periodic Table.
Within the Periodic Table, the metalloids lie diagonally from boron to polonium. Items above on the right are nonmetals, and items below on the left are metals.
The noble gases are located in group 18 of the Periodic Table.
Just make a list of rules and draw it
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.
Soil erosion has consequences that go beyond the loss of fertile land. It has resulted in an increase in contamination and sedimentation in lakes and rivers, clogging them and causing fish and other animals to decline. Degraded lands are also less capable of retaining water, which can exacerbate flooding.
Explanation:
we know that 0.250 L = 0.250 dm3
molarity = concentration in dm3/ volume
molarity = 0.175/0.250 = 0.7 mol/dm3