Answer: 20 mg Te-99 remains after 12 hours.
Explanation: N(t) = N(0)*(1/2)^(t/t1/2)
N(t) = (80 mg)*(0.5)^(12/6)
N(t) = 20 mg remains after 12 hours
Standard equation would be N2(g)+3H2(g)==>2NH3(g), so through stoichiometry, (4 mol N2)(2mol NH3/1 mol N2), assuming excess H2, would yield 8 moles of NH3.
A space-filling model shows the relative amount of space each atom takes up. In other words, a space-filling model can show relative sizes of atoms. However, unlike ball-and-stick or structural models, space-filling models do not show bond lengths clearly. Bonds are not really like sticks in a ball-and-stick model.
Answer:
In order to find the molecular formula from an empirical formula you must find the ratio of their molecular masses.
We know that the molecular mass of the molecule is 70
gmol-1
. We can calculate the molar mass of
CH2
from the periodic table:
C=12.01
gmol−1
H=1.01
gmol−1
CH2 =14.03
gmol−1
Hence we can find the ratio:
14.03
70
≈
0.2
This problem is providing us with a statement in which we need to figure out the word fitting in the blank. At the end, after analyzing the information, the word turns out to be colligative as show below:
<h3>Colligative properties.</h3>
In chemistry, colligative properties of solutions account for the behavior of a solution with respect to the pure solvent, to which a solute is added.
Among them, we have boiling point elevation, freezing point depression, vapor pressure lowering and osmotic pressure, which are all affected by the concentration of the solute but not by the identity of the solute.
In such a way, we conclude that the correct word that fits in the blank is colligative as shown below:
"Colligative properties depend on the concentration of a solute in a solution but not on the identity of the solute."
Learn more about colligative properties: brainly.com/question/10323760