Answer:
the second one looks like it so I picked the second one
The absence of standards of absolute and universal application.
Answer:
¨molecular compounds are formed by the sharing of electrons, and ionic compounds are formed by the transfer of electrons¨
Explanation:
Answer:
0.125 mg
Explanation:
<em>The correct answer would be 0.125 mg</em>
<u>According to the conversion factor, one milligram of a sample is equivalent to one thousand micrograms of the same sample.</u>
milligram = 
microgram = 
Hence,
1 milligram = 1000 micrograms or 1 microgram = milligram
Therefore, 125 micrograms will be:
125/1000 = 0.125 milligram
To solve this we use the equation,
M1V1 = M2V2
where M1 is the concentration
of the stock solution, V1 is the volume of the stock solution, M2 is the
concentration of the new solution and V2 is its volume.
M1V1 = M2V2
1% x V1 = 0.25% x 10 mL
V1 =2.5 mL
Therefore, you will need to have 2.5 mL of the 1% HCl solution and 7.5 mL of distilled water. In mixing the two liquids, you should remember that the order of mixing would be acid to water. So, you use a 10 mL volumetric flask . Put small amount of distilled water and add the 2.5 mL of HCl solution. Lastly, dilute with distilled water up to the 10 mL mark.
