Answer: The half-life of a first-order reaction is, 
Explanation:
All the radioactive reactions follows first order kinetics.
Rate law expression for first order kinetics is given by the equation:
![k=\frac{2.303}{t}\log\frac{[A_o]}{[A]}](https://tex.z-dn.net/?f=k%3D%5Cfrac%7B2.303%7D%7Bt%7D%5Clog%5Cfrac%7B%5BA_o%5D%7D%7B%5BA%5D%7D)
where,
k = rate constant = ?
t = time taken = 440 s
![[A_o]](https://tex.z-dn.net/?f=%5BA_o%5D)
= initial amount of the reactant = 0.50 M
[A] = left amount = 0.20 M
Putting values in above equation, we get:
The equation used to calculate half life for first order kinetics:
Putting values in this equation, we get:
Therefore, the half-life of a first-order reaction is,
Radio waves.
From lowest to highest it is radio wave, microwave, infrared, visible light, ultraviolet, x ray, and then gamma.
Answer:
1. 0.338 moles of Fe
2. 0.700 moles of Fe
3. 48.3%
Explanation:
This is the reaction:
Fe₂O₃ + 3C → 2Fe + 3CO
We were told that we produce 18.9 g of Fe. Let's convert the mass to moles:
18.9 g . 1mol/ 55.85 g = 0.338 moles of Fe
Let's make a rule of three; ratio is 1:2.
1 mol of oxide can produce 2 moles of elemental iron
Then, 0.350 moles must produce (0.350 .2) / 1 = 0.700 moles of Fe
Let's determine the percent yield:
(Yield produced /Theoretical Yield) . 100 = 48.3 %
<span>Elements are classified as metals, nonmetals, or metalloids according to their PHYSICAL PROPERTIES</span>
