<u>Answer:</u> The time required will be 19.18 years
<u>Explanation:</u>
All the radioactive reactions follows first order kinetics.
The equation used to calculate half life for first order kinetics:
We are given:
Putting values in above equation, we get:
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 for decay process = ?
![[A_o]](https://tex.z-dn.net/?f=%5BA_o%5D)
= initial amount of the reactant = 2 g
[A] = amount left after decay process = (2 - 0.5) = 1.5 g
Putting values in above equation, we get:
Hence, the time required will be 19.18 years
Answer: A, C, E
Explanation: PLATO. all testable questions.
Obliviously not all rocks have holes in them
It is called vesicular texture These refers to viscles holes pores or cavities within the igneous rock.the vesicles are the result of gas expansion(bubbles).which often occur during volcanic eruptions .
1 mol = 6.023x10^23 number of molecules (Avogadro's number)
1 : 6.023x10^23
X : 4.91x10^22
(6.023x10^23)X = 4.91x10^22
X = 4.91x10^22/6.023x10^23
X = 0.082 Moles
Answer:
heat flux ( Q ) = 8 W/m³ uniform heat flux throughout the block
Explanation:
flat plate ecuation with uniform source:
- d2T / dx² = - Q / k...........from general balance
- if x = 0 ⇒ dT / dx = 0 ; Q = 0
- if x = L ⇒ T = T1
∴ k = 0.04 W/mC; L = 0.2 m
If T = - 100x² + 20x
⇒ dT / dx = - 200x + 20
⇒ d2T / dx² = - 200 = - Q / k
⇒ Q / k = 200
⇒ Q = 200 * 0.04 W/mC
⇒ Q = 8 W/m³
