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3 years ago

How will you know whether a solution is saturated or supersaturated?

1 answer:

6 0

You tell tell if a solution is supersaturated if it cannot dissolve any more solute at any given temperature. You can not “mix” the solution anymore to dissolve the solute. If it is saturated, you would be able to dissolve the solute.

You might be interested in

For which one of the following reactions is the value of ΔH°rxn equal to ΔH°f for the product?

noname [10]

Answer:

The reaction D has the value of ΔH°rxn equal to ΔH°f for the product.

Explanation:

The ΔH°f for product is equal to ΔH°rxn when the reagents are in their elemental state (ΔH°f = 0) and form one mole of product.

We have to find the reagents that are in their elemental state and that only form one mole of product:

A) 2Ca (s) + O₂ (g) → 2CaO (s)

The reagents are in their elemental state but the reaction forms two mole of product.

B) C₂H₂ (g) + H₂ (g) → C₂H₄ (g)

C₂H₂ (g) is not in its elemental state.

C) 2C (graphite) + O₂ (g) → 2CO (g)

Graphite and Oxygen are in their elemental state but the reaction forms two mole of product.

D) 3Mg (s) + N₂ (g) → Mg₃N₂ (s)

Magnesium and Nytrogen are in their elemental state and the reaction forms one mole of product.

E) C (diamond) + O₂ (g) → CO₂ (g)

Diamond is not in its elemental state.

8 0

3 years ago

Compared to pure water, an aqueous solution of calcium chloride has what?

V125BC [204]

It has a higher boiling point and a lower freezing point

8 0

3 years ago

Experiment #1A melting point of an old sample of Naphthalene was completed and a melting range of 77-83 oC was observed and reco

White raven [17]

Answer:

%error = 0.32%

Explanation:

Let's answer both questions, by parts.

1. Percentage error:

In this case, I do not have the video, but I do have the reported melting point of naphtalene which is 80.26 °C.

The expression to calculate the percentage error is the following:

%Error = absolute error / actual percentage. (1)

And the absolute error is:

Abs error = actual value - experimental value (2)

But the experimental value is a range, so we just have to get a average of that:

Exp value = 77 + 83 / 2 = 80 °C

Now the absolute error:

Abs error = 80.26 - 80 = 0.26 °C

Finally the %error:

%error = (0.26 / 80.26) * 100

<h2>%error = 0.32%</h2>

2. Meaning of melting point range and %error

The melting point range just means that the sample of naphtalene has impurities, and when a sample of any compound has impurities, melting point tends to be low. However, this decrease of temperature is a wider range. But usually a range of just 5° C means that compound has little traces of impurities but it can still be used for reactions.

The %error means that the impurities of the sample are really low, so the sample is practically pure with little traces of impurities.

3 0

3 years ago

a chemist dissolves 0.564 moles of manganese (IV) oxide (MnO2) in water, and adds enough water to make 0.510 L of solution. Calc

ladessa [460]

Answer:

The molarity of the solution is 1.1 $\frac{moles}{liter}$

Explanation:

Molarity is a measure of the concentration of that substance that is defined as the number of moles of solute divided by the volume of the solution.

The molarity of a solution is calculated by dividing the moles of the solute by the volume of the solution:

$molarity=\frac{number of moles of solute}{volume}$

Molarity is expressed in units $\frac{moles}{liter}$

In this case

number of moles of solute= 0.564 moles
volume= 0.510 L

Replacing:

$molarity=\frac{0.564 moles}{0.510 L}$

Solving:

molarity= 1.1 $\frac{moles}{liter}$

<u><em>The molarity of the solution is 1.1 </em></u> $\frac{moles}{liter}$ <u><em></em></u>

4 0

3 years ago

A flask at room temperature contains exactly equal amounts (in moles) of nitrogen and xenon.

zalisa [80]

Answer:

a) Same

b) Nitrogen

c) Same

d) Nitrogen

Explanation:

The formula for partial pressure of a gas is equal to

$p_B = n_B \frac{RT}{V}$

Here nB is the number of moles .

The number of moles for both the gases are same and hence the partial pressure for the two gases will also be same.

b) The greater average velocity is calculated by using following formula

$v_{RMS} = \sqrt{3RTM}$

Here M is the molar mass.

Molar mass of nitrogen is greater than the molar mass of xenon and hence nitrogen will have higher greater average velocity

c) As we know, the average kinetic energy of gas particles is dependent on the absolute temperature of gas and if all the gases are at same temperature, their kinetic energy will also be same. Since nitrogen and xenon are at same temperature, their kinetic energy will be same

d) Effusivity is depended directly on the thermal conductivity, density and and the specific heat capacity.

All these three parameters are higher in case of nitrogen. Thus, it will effuse first

4 0

3 years ago