A boy lifts a 30N dragon 2 meters above the ground. How much work did the boy do on the dragon?

In pure water at 25 °C, the concentration of a saturated solution of CuF2 is 7.4 × 10−3 M. If measured at the same temperature,

Romashka-Z-Leto [24]

Answer:

The concentration of a saturated solution of CuF₂ in aqueous 0.20 M NaF is 4.0×10⁻⁵ M.

Explanation:

Consider the ICE take for the solubility of the solid, CuF₂ as:

CuF₂ ⇄ Cu²⁺ + 2F⁻

At t=0 x - -

At t =equilibrium (x-s) s 2s

The expression for Solubility product for CuF₂ is:

$K_{sp}=\left [ Cu^{2+} \right ]\left [ F^- \right ]^2$

$K_{sp}=s\times {2s}^2$

$K_{sp}=4s^3$

Given s = 7.4×10⁻³ M

So, Ksp is:

$K_{sp}=4\times (7.4\times 10^{-3})^3$

Ksp = 1.6209×10⁻⁶

Now, we have to calculate the solubility of CuF₂ in NaF.

Thus, NaF already contain 0.20 M F⁻ ions

Consider the ICE take for the solubility of the solid, CuF₂ in NaFas:

CuF₂ ⇄ Cu²⁺ + 2F⁻

At t=0 x - 0.20

At t =equilibrium (x-s') s' 0.20+2s'

The expression for Solubility product for CuF₂ is:

$K_{sp}=\left [ Cu^{2+} \right ]\left [ F^- \right ]^2$

$1.6209\times 10^{-6}={s}'\times ({0.20+2{s}'})^2$

Solving for s', we get

s' = 4.0×10⁻⁵ M

The concentration of a saturated solution of CuF₂ in aqueous 0.20 M NaF is 4.0×10⁻⁵ M.

3 0

2 years ago

The radius of a potassium atom is 231 pm. How many potassium atoms would have to be laid side by side to span a distance of 4.77

Softa [21]

To determine the number of potassium laid side by side by a given distance, we simply divide the total distance to the diameter of each atom. The diameter is twice the radius of the atom. We calculate as follows:

number of atoms = 4770 / 231x10^-12 = 2.06x10^13 atoms

3 0

2 years ago

Read 2 more answers

A 5 mole sample of liquid acetone is converted to a gas at 75.0°C. If 628 J are required to raise the temperature of the liquid

Shkiper50 [21]

The total energy can be found by adding the different energies:
628 + 15,600 + 712
= 16.94 kJ

4 0

2 years ago

An archaeologist discovers an ancient wooden bowl. which isotope would most likely be used to determine its age?

Vesnalui [34]

Answer:

c

Explanation:

whdkcbwubcdw

7 0

1 year ago

Read 2 more answers

What is the number of moles in 15.0 g AsH3?

Grace [21]

Answer:

0.192 mol.

Explanation:

To calculate the no. of moles of a substance (n), we use the relation:

n = mass / molar mass.

mass of AsH₃ = 15.0 g.

molar mass of AsH₃ = 77.95 g/mol.

∴ The number of moles in 15.0 g AsH₃ = mass / molar mass = (15.0 g) / (77.95 g/mol) = 0.192 mol.

7 0

1 year ago