We are asked to convert 25 cg to units of hg.
1 cg = 1 centigram = 10⁻² g
1 hg = 1 hectogram = 10² g
The options given are:
a) 1 hg/ 10² g
b) 10² cg/ 1 hg
c) 10² hg/ 1 cg
d) 10⁻² g/ 1 cg
To convert 25 cg to 1 hg, we could convert the 25 cg to grams first, then grams to hg.
25 cg · 10⁻² g/ 1cg = 0.25 g
Here we have converted our number from cg to grams. We can use another conversion of grams to hg to complete the conversion.
0.25 g · 1 hg/ 10² g = 0.0025 hg
Therefore, the first conversion we used was d) 10⁻² g/ 1 cg.
On the other hand ammonia is a very dangerous chemical which has a pungent smell and effect the eyes of the user. Thus it kept always in the fume exhaust hood for storing and dispensing function.
The pH of ammonia buffer contains ammonium hydroxide (NH₄OH) and a salt of ammonia with a strong acid like (HCl) which produces, ammonium chloride (NH₄Cl) mixture. The evaporation rate of ammonia is so high at room temperature thus on opening of the buffer solution the ammonia get evaporated very fast and the concentration of ammonia decreases which affect the pH of the buffer solution.
Thus the reason to put ammonia buffer in fume hood is explained.
Answer:
616,0 ng is the right answer.
Explanation:
You should know that 1 mole = 1 .10^9 nanomoles
Get the rule of three.
1 .10^9 nanomoles ...................... 56.0 gr
11 nanomoles .....................
(11 x 56) / 1 .10^9 nanomoles = 6.16 x 10^-7 gr
Let's convert
6.16 x 10^-7 gr x 1 .10^9 = 616 ngr
C) Tc-99 is a radioactive isotope also known as radioisoptope.