Answer:
B) a chemical change .
Explanation:
There will be no chemical reaction when the gases ammonia and carbon dioxide are mixed together . But when there is presence of ammonium hydroxide , chemical reaction takes place between carbon dioxide and ammonium hydroxide resulting into the formation of ammonium carbonate as follows
2NH₄OH + CO₂ =( NH₄)₂CO₃ + H₂O.
The growth of white crystals inside the bottle indicates the presence of ammonium carbonate .
So it is a chemical change .
Answer:
2v
Explanation:
The function of the velocity is:
v = v0 + a.t, where v is the top speed, v0 is the initial speed, a is the acceleration and t the time.
Both the tortoise and the hare start at rest, so v0 = 0. For the tortoise:
v = a.t
For the hare:
v' = a't', but a' = a and t' = 2t
v' = a*2t
v' = 2*at
v' = 2v
Because those layers have been in existence longer than the layer on top of it.
Convex lenses bulge<span> out in the </span>middle<span> </span>
Answer:
The De Broglie wavelength decreases
Explanation:
The relationship between the De Broglie wavelength of a particle and its momentum is given by
where
is the De Broglie wavelength of the particle
h is the Planck constant
p is the momentum of the particle
As we see from the formula, there is an inverse relationship between the De Broglie's wavelength and the momentum. Therefore, we can conclude that:
- if the momentum of the electron increases,
- its De Broglie wavelength will decrease
and vice-versa.