In general terms, exothermic reactions release energy, so the energy goes from the system to the surroundings.
<u>Answer:</u> The given chemical reaction can be classified as synthesis and exothermic.
<u>Explanation:</u>
A synthesis reaction is defined as the reaction where two small chemical species combine in their elemental state to form a single large chemical species.
Exothermic reactions are defined as the reactions in which heat is released by the reaction. The heat is written on the product side of the reaction.
For the given chemical reaction:

The above chemical reaction is a type of synthesis and exothermic as two substances in their elemental state are combining. Also, heat is getting released in the reaction.
Hence, the given chemical reaction can be classified as synthesis and exothermic.
Answer:
k = 1.3 x 10⁻³ s⁻¹
Explanation:
For a first order reaction the integrated rate law is
Ln [A]t/[A]₀ = - kt
where [A] are the concentrations of acetaldehyde in this case, t is the time and k is the rate constant.
We are given the half life for the concentration of acetaldehyde to fall to one half its original value, thus
Ln [A]t/[A]₀ = Ln 1/2[A]₀/[A]₀= Ln 1/2 = - kt
- 0.693 = - k(530s) ⇒ k = 1.3 x 10⁻³ s⁻¹
An electron in the 3s orbital. The order of electron orbital energy levels starting from lowest to highest is as follows: 1s, 2s, 2p, 3s, 3p, 4s, 3d, 4p, 5s, 4d, 5p, 6s, 4f, 5d, 6p, 7s, 5f, 6d, 7p.