Aspectrum for a given element is unique for that element. why is that so?
a. no element has more than 2 electrons in the first shell.
b. each element has an unique arrangment of electrons
c. atoms of different elements have different masses
d. atom nuclei contains no electrons

Modern whales developed their traits through natural selection what occurs during the process of natural selection

Select the correct answer from each drop-down menu. in an experiment, dr. travis examined the effects of calcium intake on osteoporosis, a condition that causes an increased risk of bone fractures. the amount of calcium is variable. the risk of bone fractures .

The graph below compares the rates of reaction of a burning candle and an exploding firework. comparing chemical reactions what can you conclude from the graph? the reaction that causes a firework to explode requires less energy to start, and occurs more rapidly than the reaction that causes a candle to burn. the reaction that causes a firework to explode requires less energy to start, and occurs less rapidly than the reaction that causes a candle to burn. the reaction that causes a firework to explode requires more energy to start, and occurs less rapidly than the reaction that causes a candle to burn. the reaction that causes a firework to explode requires more energy to start, and occurs more rapidly than the reaction that causes a candle to burn. mark this and return