Answer:
1 day
Explanation:
Let the safe level = x
The current level = x + 0.2x = 1.2 x
Thus,
Half life = 3.8 days
Where, k is rate constant
So,
The rate constant, k = 0.1824 days⁻¹
Using integrated rate law for first order kinetics as:
Where,
is the concentration at time t
is the initial concentration
So,
= x / 1.2 x = 0.8333
t = ?
t ≅ 1 day
<u>Lab must be vacated in 1 day.</u>
Answer:
The heat flux between the surface of the pond and the surrounding air is<em> 60 W/</em><em> </em>
Explanation:
Heat flux is the rate at which heat energy moves across a surface, it is the heat transferred per unit area of the surface. This can be calculated using the expression in equation 1;
q = Q/A ...............................1
since we are working with the convectional heat transfer coefficient equation 1 become;
q = h () ........................2
where q is the heat flux;
Q is the heat energy that will be transferred;
h is the convectional heat coefficient = 20 W/.K;
is the surface temperature =
C 23°C + 273.15 = 296.15 K;
is the surrounding temperature =
C = 20°C + 273.15 = 293.15 K;
The values are substituted into equation 2;
q = 20 W/.K ( 296.15 K - 293.15 K)
q = 20 W/.K ( 3 K)
q = 60 W/
Therefore the heat flux between the surface of the pond and the surrounding air is 60 W/