Formula is moles =massin grams of HNO3/molar mass of HNO3
The answer could honestly be as simple as "Putting rock salt on the roads during a snowstorm is an example of a chemical reaction" but due to lack of context I'm not sure, hope this helps anyways!
Answer:
0.0428 M
Explanation:
Because we're asked to calculate the molarity of nickel(II) cation, we need to <u>determine all sources for that species</u>, in this case, all Ni⁺² comes from the nickel(II) bromide solid (NiBr₂).
We use the molecular weight of NiBr₂ to calculate the moles of Ni:
1.87 g NiBr₂ ÷ 218.49g/mol * (1molNi⁺²/1molNiBr₂) = 8.55x10⁻³ mol Ni⁺²
Then we <u>divide the moles by the volume in order to calculate the concentration</u>:
8.55x10⁻³ mol Ni⁺² / 0.200 L = 0.0428 M
Given,
P1 = 0.98 atm
V1 = 0.5 L
V2 = 1.0 L
P2 = ?
Solution,
According to Boyle's Law,
P1V1 = P2V2
0.98 × 0.5 = 1.0 × P2
P2 = 0.98 × 0.5 × 1.0
P2 = 0.49 atm
Answer - The new pressure is 0.49 atm.