Answer:
idk but this is what i know only
Explanation:
he half-life is the amount of time it takes for one-half of an isotope sample to decay into a different element. The half-life of 238U is 4.5 billion years. Other radioactive isotopes decay in a much shorter time. By comparison, the half-life of 14C (carbon 14) is approximately 5,700 years. Radiometric dating has calculated the age of the earth at 215 approximately 4.6 billion years. 1. Which circle in Figure 13-2 represents the amount of the original isotope before decay began?A 2. Assume that Figure 13-2 represents the half-life of 238U. Color in the area of circles B, C, and D that represents the amount of 238U remaining in the rock layer as each half-life passes. 3. If Figure 13-2 represented the half-life of 238U, which circle that you colored would represent a rock layer with the greatest concentration of lead? _A__ 4. Which circle that you colored shows the amount of the original isotope remaining after two half-life periods have expired? 5. IT Figure 13-2 represented the half-life of 14C, how many years would have passea to reach letter D? years 70 um ens ghe ting Fie ni boe nibs D rlt to got no oA teB Lgoc velFIGURE 13-2. Half-Life of a Radioactive Isotope C teob
Mass number = number of protons + number of neutrons
The number of protons in the nucleus of an atom of phosphorus is equal to the atomic number of phosphorus, which is 15. If an atom of phosphorus has 17 neutrons, then the mass number would be 15 protons + 17 neutrons = 32. Thus, the correct answer choice here is B.
Answer:
it’s D.The cake is formed by a chemical change and the icing is formed by a physical change
Explanation:
It’s because when the cake was baking there was nothing physical about it so it was a chemical change the icing is formed by a physical change because all you did was mix three ingredients together
It would be water. Since the body is 60-75% water, it is important in chemical reactions within the body.
