Which is a complex molecule? a. H2 b. Ne c. Co d. H20

328. mL of 0.00345 M NaI (aq) is combined with 703. mL of 0.00802 M Pb(NO3)2 (aq). Determine if a precipitate will form given th

Vsevolod [243]

Answer:

The solution will not form a precipitate.

Explanation:

The Ksp of PbI₂ is:

PbI₂(s) ⇄ 2I⁻(aq) + Pb²⁺(aq)

Ksp = 1.40x10⁻⁸ = [I⁻]²[Pb²⁺] Concentrations in equilibrium

When 328mL of 0.00345M NaI(aq) is combined with 703mL of 0.00802M Pb(NO₃)₂. Molar concentration of I⁻ and Pb²⁺ are:

[I⁻] = 0.00345M × (328mL / (328mL+703mL) = 1.098x10⁻³M

[Pb²⁺] = 0.00802M × (703mL / (328mL+703mL) = 5.469x10⁻³M

Q = [I⁻]²[Pb²⁺] Concentrations not necessary in equilibrium

If Q = Ksp, the solution is saturated, Q > Ksp, the solution will form a precipitate, if Q < Ksp, the solution is not saturated.

Replacing:

Q = [1.098x10⁻³M]²[5.469x10⁻³M] = 6.59x10⁻⁹

As Q < Ksp, the solution is not saturated and will not form a precipitate.

6 0

3 years ago

If a sample of gas is at 672 °C and 3.9 atm, what is the new temperature at 12.2 atm?

Snowcat [4.5K]

In order to calculate the final temperature of the gas, we may apply Charles's law, which states that the pressure and temperature of a fixed amount of gas at constant volume are directly proportional. Mathematically:
P/T = constant
(absolute temperature is used, so T = 672 + 273 = 945 K)
Thus,
3.9 / 945 = 12.2 / T
T = 2,956 K or 2,683 °C

7 0

3 years ago

On a mission to a newly discovered planet, an astronaut finds gallium abundances of 61.29 % for 69Ga and 39.71 % for 71Ga. What

snow_lady [41]

I believe it is 70.281amu

8 0

3 years ago

What would be the major product obtained from hydroboration–oxidation of the following alkenes?

zmey [24]

Answer:

a. 3-methylbutan-2-ol

b. 2-methylcyclohexan-1-ol

Explanation:

For this reaction, we must remember that the hydroboration is an "anti-Markovnikov" reaction. This means that the "OH" will be added at the least substituted carbon of the double bond.

In the case of 2-methyl-2-butene, the double bond is between carbons 2 and 3. Carbon 2 has two bonds with two methyls and carbon 3 is attached to 1 carbon. Therefore the "OH" will be added to carbon three producing 3-methylbutan-2-ol.

For 1-methylcyclohexene, the double bond is between carbons 1 and 2. Carbon 1 is attached to two carbons (carbons 6 and 7) and carbon 2 is attached to one carbon (carbon 3). Therefore the "OH" will be added to carbon 2 producing 2-methylcyclohexan-1-ol.

See figure 1

I hope it helps!