Answer:
D
Explanation:
I hope this right, I'm sorry if it's not.
For an atom to be neutral, it has to have the same amount of protons and electrons. Because protons and electrons have opposite charges, when there is an equal amount of them they balance each other out
The original mass of krypton 81 that is present in the ice is 6.70 grams.
<h3>How do we calculate original mass?</h3>
Original mass of any substance will be calculated as below for the decomposition reaction is:
N = N₀(1/2)ⁿ, where
N = remaining mass of krypton-81 = 1.675g
N₀ = original mass of krypton-81 = ?
n will be calculated as:
n = T/t, where
T = total time period = 458,000 years
t = half life time = 229,000 years
n = 458,000/229,000 = 2
Now putting all these values on the above equation, we get
N₀ = 1.675 / (1/2)²
N₀ = 6.70 g
Hence required mass is 6.70 g.
To know more about half life time, visit the below link:
brainly.com/question/2320811
Evaporation is called a surface phenomenon because water molecules present on the surface of liquid are bonded weakly as compared to inner molecules and when temperature increase hydrogen bonding between molecules break .Due to this water molecules tend to evaporation so that's why evaporation called the surface phenomenon.