Answer:
The equilibrium expression is:
CoC2O4(s)⇌Co2+(aq)+C2O2−4(aq)
For this reaction:
Ksp = [Co2+][C2O2−4]=1.96×10−8
Explanation:
Batteries will not clot if cobalt ions are removed from its cells. Some blood collection tubes contain salts of the oxalate ion,
C2O2−4
, for this purpose. At sufficiently high concentrations, the calcium
and oxalate ions form solid, CoC2O4·H2O (which also contains water bound in the solid). The concentration of Co2+ in a sample of blood serum is 2.2 × 10–3M. What concentration of
C2O2−4
ion must be established before CoC2O4·H2O begins to precipitate.
CoC2O4 does not appear in this expression because it is a solid. Water does not appear because it is the solvent.
Solid CoC2O4 does not begin to form until Q equals Ksp. Because we know Ksp and [Co2+], we can solve for the concentration of
C2O2−4
that is necessary to produce the first trace of solid:
Answer:
1.72x10⁻⁵ g
Explanation:
To solve this problem we use the PV=nRT equation, where:
- R = 0.082 atm·L·mol⁻¹·K⁻¹
- T = 25 °C ⇒ (25+273.16) = 298.16 K
And we <u>solve for n</u>:
- 1 atm * 5.7x10⁶ L = n * 0.082 atm·L·mol⁻¹·K⁻¹ * 298.16 K
Finally we <u>convert moles of helium to grams</u>, using its <em>molar mass</em>:
- 4.29x10⁻⁶ mol * 4 g/mol = 1.72x10⁻⁵ g
Answer:
105m/3hourz
Explanation:
35 miles per hour, so 3 hours
35x3=105 per 3 hours
Answer:
12,742 km
Explanation:
Therefore, its radius is 6,371 km.