Answer:
[NO₃⁻ ] = 2.596 M
Explanation:
Ca(NO₃)₂ dissolves in water according to the following equation:
Ca(NO₃)₂ ⇒ Ca²⁺ + 2NO₃⁻
The moles of Ca(NO₃)₂ that dissolve is found as followed:
(21.3 g) / (164.10 g/mol) = 0.1298... mol
The number of NO₃⁻ ions are related to the above quantity by the molar ratio:
(0.1298 mol Ca(NO₃)₂) (2NO₃⁻/Ca(NO₃)₂) = 0.2596...mol NO₃⁻
The concentration of the nitrate ions is then calculated:
[NO₃⁻ ] = (0.2596...mol) / (100.0ml) x (1000mL/L) = 2.596 M
Here Is A Sentence You Could Possibly Use:
"The most common usage of non-contact force is weight."
Hope This Helps!
BTW, You May Want A Second Opinion Just In Case! :)
Answer:
the ans is option b(help navigate at night)
The most logical answer is d
The integrated rate law expression for a first order reaction is
![ln\frac{[A_{0}]}{[A_{t}]}=kt](https://tex.z-dn.net/?f=ln%5Cfrac%7B%5BA_%7B0%7D%5D%7D%7B%5BA_%7Bt%7D%5D%7D%3Dkt)
where
[A0]=100
[At]=6.25
[6.25% of 100 = 6.25]
k = 9.60X10⁻³s⁻¹
Putting values
taking log of 100/6.25
100/6.25 = 16
ln(16) = 2.7726
Time = 2.7726 / 0.0096 = 288.81 seconds
