Answer:
k_2 = 7.815 * 10^-3 s^-1
Explanation:
Given:
- rate constant of reaction k_1 = 7.8 * 10^-3 s^-1 @ T_1 = 25 C
- rate constant of reaction k_2 = ? @ T_2 = 75 C
- The activation energy E_a = 33.6 KJ/mol
- Gas constant R = 8.314472 KJ / mol . K
Find:
- rate of reaction k_2 @ T_2 = 75 C
Solution:
- we will use a combined form of Arrhenius equations that relates rate constants k as function of E_a and temperatures as follows:
k_2 = k_1 * e ^ [(E_a / R) * ( 1 / T_1 - 1 / T_2 )
- Evaluate k_2 = 7.8 * 10^-3* e^[(33.6 / 8.314472)*(1/298 -1/348)
- Hence, k_2 = 7.815 * 10^-3 s^-1
Answer:
D. Hydrogen combines with oxygen to form water.
Explanation:
Hydrogen combining with oxygen to form water is a typical example of chemical reaction.
During a chemical reaction, atoms of elements are rearranged. Most chemical reactions obey the law of conservation of mass which states that "matter is neither created nor destroyed in a chemical reaction but atoms are simply rearranged".
The other choices given are nuclear reactions. In such reactions, atoms are not rearranged but are simply destroyed and made in the process.
<span>try y =kx
and find value of k
by substituing x and y from the table</span>
If y<span>ou are going to invent a new device that people can use instead of a microwave oven to warm up leftovers, the type of electromagnetic wave that would be most useful to investigate would probably be infrared waves, because these kinds of waves are associated with heat. </span>
Answer:
Vf = 21.5 [m/s]
Explanation:
To solve this problem we must use the following kinematics equation:
where:
Vf = final velocity [m/s]
Vi = initial velocity = 0
a = aceleration = 4.3 [m/s^2]
t = time = 5 [s]
Now replacing:
Vf = 0 + (4.3*5)
Vf = 21.5 [m/s]
