Answer:
3
Explanation:
Applying,
= R/R'............... Equation 1
Where n' = number of halflives that have passed, R = Original atom of the substance, R' = atom of the substance left after decay.
From the question,
Given: R = 40 atoms, R' = 5 atoms
Substitute these values into equation 1
= 40/5
= 8
= 2³
Equation the base,
n' = 3
Answer:
B. exothermic; leaving
Explanation:
The exothermic process releases heat, which causes the surrounding area to increase in temperature.
Your hand is releasing heat and makes the temperature of the ice cube increase, to where it melts.
It is going through a physical change
Density * Volume = Mass
Now we substitute the values in.
19.3 g/cm^3 + 20 cm^3 = 386 g
Mass = 386 g
