Answer:carbon-14 levels in the atmosphere
Explanation:
When carrying out radiocarbon dating, the level of carbon-14 in a sample is compared with the level of carbon 14 in the atmosphere because, objects exchange carbon-14 with the atmosphere.
Comparison of the activities of carbon-14 in the atmosphere and in the sample gives the age of the sample since the half-life of carbon-14 is a constant.
I think that the answer is A because if you think about water for an example. When water turns into ice, it's still technically water, just the molecules are frozen. The water is physically changed. It could also see why you think it is B but I don't think so completely. It doesn't really make sense to me. So I'd choose A. It's definitely not C or D.
Complete Question:
Suppose a cobalt atom in the +3 oxidation state formed a complex with two bromide (Br-) anions and four ammonia (NH3) molecules. write the chemical formula of this complex.
Answer:
[Co(NH₃)₄]⁺Br₂
Explanation:
The cobalt atom with +3 oxidation is represented as Co⁺³, and if it's bonded to two bromide ions, and four ammonia molecules. The molecules that are bonded to the metal atom (Co) are called complexing agents.
In the representation, we first put the molecules that surround the metal atom, forming an anion with the oxidation of the metal:
[Co(NH₃)₄]⁺³
Then, the ions are put in the formula. Because there are two bromides ion, each one with 1 minus charge, only 2 plus charged will be neutralized, and the complex will be:
[Co(NH₃)₄]⁺Br₂
Answer:
<h3>
C. 3</h3>
Explanation:
there are three electrons in a 2p sub-energy level of s neutral nitrogen atom.
A.) independent variable.
the control was or would be the plant at the window. the dependent is the growth of each plant. the constant is the amount of water
