The correct answer would be equation 4, because there are 4 Hydrogens and 2 Oxygens on each side of the equation making it balanced.
The correct lewis structure of methane(CH4)
C. H:C:H:H
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
Answer:
Please check again, there is no file attached
A) a compressed spring in a pinball machine just before the ball is launched