Answer:
After 90 minutes 5.15625 g amount left from total of 165 g.
Explanation:
Given data:
Technetium-104 half life = 18.0 min
Total amount of sample = 165 g
Amount left after 90.0 min = ?
Solution:
First of all we will calculate the number of half lives passes.
Number of half lives = T elapsed / Half life
Number of half lives = 90 min /18.0 min
Number of half lives = 5
Amount left:
At time 0 = 165 g
At first half life = 165 g/ 2= 82.5 g
At 2nd half life = 82.5 g/2 = 41.2 g
At 3rd half life = 41.2 g/ 2 = 20.625 g
At 4th half life = 20.625 g/ 2 = 10.3125 g
At 5th half life = 10.3125 g /2 = 5.15625 g
Thus, after 90 minutes 5.15625 g amount left from total of 165 g.
As we know that
<span>V1/T1 = V2/T2
V1 = 9.10 L
T1 = 471 K
V2 = 2.50 L
T2 = 2.5 x 471 / 9.10 = 129.3 K
T2 = 129.3 - 273 =
-143.6 deg Celsiu
hope it helps</span>
To get moles. divide mass by molar mass.Molar mass of
Na is 23
and for Cl is 35.5.
the total molar mass of NaCl is 23+35.5 = 58.5mol/gUse the mass and divide by this number30.22g divide by 58.5mol/g and you will get 0.5166 mole.
Since the molecule has 1 Na to 1 Cl, and that the number of moles for NaCL is 0.5166. All of them would be 0.5166molesNa = 0.5166 x 1 = 0.5166molesCl = 0.5166 x 1 = 0.5166moles
to get number of atoms. Multiply your mole by Avogadro number which is 6.022x10^23Na = 0.5166 x 6.022E23 = 3.111x10^23Cl = 0.5166 x 6.022E23 = 3.111x10^23
D. Polyacrylonitrite
hope i help my bad if i'm wrong
For a reaction system at equilibrium, LeChatelier's principle can be used to predict the "effect of a stress on the system".
<u>Option: C</u>
<u>Explanation:</u>
Le Chatelier's theory can be implemented to forecast a system's behavior due to variations in pressure, temperature, or concentration that will lead in predictable and contested variations in the system adjustments to establish a new state of equilibrium. This means that adding heat to a process would favor the endothermic path of a reaction, because this decreases the amount of heat generated in the system.
Here shift in equilibrium take place when volume increase, the total pressure decreases, which have potential to reverse the reaction, while on increasing pressure of system, the total volume decreases of the gaseous system, which can shift an equilibrium in the direction of the fewer molecules.
