Answer:
The answer to your question is:
Explanation:
Data
Atomic number = Z = 28
Mass number = A = 152
Atomic number number = # of protons
Mass number = # of protons + # of neutrons
Then
Protons = 28
Electrons = 28
Neutrons = 152 - 28 = 124
Answer:
it is the objects mass, I learned this last semester
Answer:
-1071 Joules
Explanation:
The Joule was introduced as the SI unit for energy in 1925. One calorie is equal to approximately 4.184 joules(J). This is a conversion factor that we can write two ways:
(1cal/4.184J) or (4.184J/1cal)
(265 cal)*(4.184J/1cal) = 1071 J
Since the energy is leaving the system, it should be written with a minus sign: -1071J
Answer and Explanation:
It's very important to assume that the rate of radioactive decay will remain constant over time to make scientists' lives easier when calculating the ages of fossils, compounds, etc.
If the rate changes, it would be extremely challenging for people to figure out the relative ages of rock strata, fossils, or other substances with radioactive elements in them. This is a fundamental assumption in order to be able to use radioactive dating.
Hope this helps!