Half-life is the time required for the amount of something to fall to half its initial value. This term is usually used in nuclear physics to describe how quickly unstable atoms undergo decay, or how long stable atoms survive, radioactive decay, and it is also used more generally of any type of exponential or non-exponential decay.
In simpler terms: this is when an isotopes radioactivity is cut in half
Since you didn't have any extra information about the question I'll be presenting an example from my own textbooks that I've used.
An example of a direct observation is listening to a cricket chirp at night, and counting the number of chirps per minute.
Direct Observation is where the evaulator watches the subject in their usual habitat without disrupting or altering it.
Answer:
56500J
Explanation:
Given parameters:
Mass of water = 25g = 0.025kg
Temperature of the water = 100°C
Unknown:
Amount of heat required to vaporize the water = ?
Solution:
The amount of heat required to vaporize the water is a function of the mass of the water and the latent heat of vaporization of water.
H = mL
H is the amount of heat
m is the mass
L is the latent heat of vaporization of water = 22.6 x 10⁵J/Kg
H = 0.025 x 22.6 x 10⁵ = 56500J
Answer:
potassium I believe is the correct answer
Explanation:
Potassium is the period four element with the lowest mass; its average mass is 39.0983amu.
Answer is no
The chemical reaction between iron and oxygen in the presence of moisture or water produces a new substance, which is the rust (iron oxide). In this case, it shows a chemical property.
