The rate constant : k = 9.2 x 10⁻³ s⁻¹
The half life : t1/2 = 75.3 s
<h3>Further explanation</h3>
Given
Reaction 45% complete in 65 s
Required
The rate constant and the half life
Solution
For first order ln[A]=−kt+ln[A]o
45% complete, 55% remains
A = 0.55
Ao = 1
Input the value :
ln A = -kt + ln Ao
ln 0.55 = -k.65 + ln 1
-0.598=-k.65
k = 9.2 x 10⁻³ s⁻¹
The half life :
t1/2 = (ln 2) / k
t1/2 = 0.693 : 9.2 x 10⁻³
t1/2 = 75.3 s
Answer:
0.6522 mol/L.
Explanation:
<em>Molarity is defined as the no. of moles of a solute per 1.0 L of the solution.</em>
<em />
M = (no. of moles of solute)/(V of the solution (L)).
<em>∴ M = (no. of moles of solute)/(V of the solution (L)) </em>= (1.5 mol)/(2.3 L) = <em>0.6522 mol/L.</em>
Answer: 1560632 joules
Explanation:
The change in thermal energy (Q) required to heat ice depends on its Mass (M), specific heat capacity (C) and change in temperature (Φ)
Thus, Q = MCΦ
Given that:
Q = ?
Mass of frozen water (ice) = 1kg
C = 4184 J/(kg K)
Φ = (Final temperature - Initial temperature)
= 100°C - 0°C = 100°C
Convert 100°C to Kelvin
(100°C + 273) = 373K
Then, Q = MCΦ
Q = 1kg x 4184 J/(kg K) x 373K
Q = 1560632 joules
Thus, the change in thermal energy is 1560632 joules
Answer:
17.6
Explanation:
Answer is explained above