Potassium burns a violet color
Answer:
I think the answer is chemical energy
Explanation:
<h2>Hello!</h2>
The wave with the lowest frequency is the second one.
<h2>Why?</h2>
Frequency is defined as the number of times that a periodic phenomenon is repeated in a given time. Regarding waves, the frequency of a wave is the number of times that a wave repeats in a unit of time. Frequency is measured in Hertz (Hz=1/s).
The relationship between frequency and wavelength is inverse, meaning that longer wavelengths mean lower frequencies. From the given list, the wave with the longest wavelength is the second one, meaning that its frequency is the lower.
Have a nice day!
C.
Water is polar because one side of the molecule is positive and the other is negative.
Answer:
Ca(OH)2 will not precipitate because Q<Ksp
Explanation:
Ksp for Ca(OH)2 has already been stated in the question as 8.0 x 10-8mol2dm-6
The value of the reaction quotient depends heavily on the concentration of the reactants. As the initial concentration of the calcium carbide decreases considerably, the reaction quotient decreases until Q<Ksp hence the Ca(OH)2 will not precipitate from solution.
The reaction equation is:
CaC₂(s) + H₂O ⇒ Ca(OH)₂ + C₂H₂
From
Ca(OH)2= Ca2+ + 2OH-
Concentration of solution= 0.064×1/64= 1×10-3
Since [Ca2+] = 1×10-3
[OH-]= (2×10-3)^2= 4×10^-6
Hence Q= 4×10^-9
This is less than the Ksp hence the answer.
