Answer:
3.816 × 10⁻³ M
Explanation:
A stock solution of Cu²⁺(aq) is made by dissolving 0.8875 g of solid Cu(NO₃)₂∙2.5H₂O in a 100.0-mL volumetric flask, and then brought up to volume with water. What is the molarity (in M) of Cu²⁺(aq) in this stock solution?
We can derive the following relations:
- The molar mass of Cu(NO₃)₂∙2.5H₂O is 232.59 g/mol.
- Each mole of Cu(NO₃)₂∙2.5H₂O yields one mole of Cu²⁺.
The moles of Cu²⁺ present in 0.8875 g of Cu(NO₃)₂∙2.5H₂O are:
The molarity of Cu²⁺ is:
Although I may not be the smartest, I can definitely answer.
This represents a chemical change because the substances' chemical identities were altered. The fizzing was a clear sign, and the temperature increase was another indicator of the reaction.
Halogens are characterized as a group of 7 on the periodic table. Each of these elements has 7 valence electrons, needing just one additional electron to fill their outer shell, resulting in their high reactivity. Moreover, the periodic law indicates that when the elements are arranged by increasing atomic number, similar patterns in their properties emerge. Thus, halogens exhibit comparable behaviors during chemical reactions with one another, which is indeed accurate.
