Bond energy:

Gabriel and his friend found a piece of metal which they want to

Dominik [7]

50/5.2 that’s the equation that you have to solve then whatever comes out yo calculator is the answer

6 0

2 years ago

Plot your values of ln(Ksp) vs. 1/T and find the slope and y-intercept of the best fit line. Use the equation for the best fit l

labwork [276]

Answer:

a) The slope of the line of best fit plot = -12629.507

b) ΔH∘ = 105 kJ

c) Intercept of the line of best fit plot = 39.099

d) ΔS∘ = 325.1 J/K

e) Option A is correct.

Solubility will increase as temperature increases, because as T increases the (−ΔH∘/RT) term becomes smaller therefore K will get larger.

f) Option D is correct. All of the options are correct.

Explanation:

The complete question is presented in the first attached image to this question. This complete question has the data readings required to plot the graph.

The second attached image has the plotted graph and the regression analysis to obtain the line of best fit.

The equation of the line of best fit obtained is

y = -12629.507x + 39.099

Comparing the given expression for the question with the equation of a straight line

ln (K) = (−ΔH∘/RT) + (ΔS∘/R)

y = mx + c

y = In K

Slope = m = (−ΔH∘/R)

x = (1/T)

Intercept = c = (ΔS∘/R)

So, to answer the question now

a) The slope of the line of best fit plot = -12629.507

b) Slope = (−ΔH∘/R)

(−ΔH∘/R) = -12629.507

But R = molar gas constant = 8.314 J/mol.K

ΔH∘ = 12629.507 × 8.314 = 105,001.721198 J = 105,002 J = 105 kJ

c) Intercept of the line of best fit plot = 39.099

d) Intercept = (ΔS∘/R)

(ΔS∘/R) = 39.099

ΔS∘ = 39.099 × 8.314 = 325.069086 J/K = 325.1 J/K

e) Do you expect the solubility of Borax to increase or decrease as temperature increases?

Solubility will increase as temperature increases, because as T increases the (−ΔH∘/RT) term becomes smaller therefore K will get larger.

f) Why was it necessary to make sure that some solid was present in the main solution before taking the samples to measure Ksp? Select the option that best explains why.

A. To make sure no more sodium borate would dissolve in solution.

B. To ensure the dissolution process was at equilibrium.

C. To make sure the solution was saturated with sodium and borate ions.

D. All of the above

Hope this Helps!!!

5 0

3 years ago

The Lewis dot notation for two atoms is shown.

Iteru [2.4K]

Answer:

Mg donates two electrons to O

Explanation:

Lewis dot notation uses dots and crosses to represent valence electrons on atoms.

Magnesium is a metal and would donate or lose electrons during bonding.

Oxygen is a non metal and would gain electrons during bonding.

The correct option is;

Mg donates two electrons to O

5 0

2 years ago

Automotive air bags inflate when sodium azide, NaN3, decomposes explosively to its constituent elements. How many moles of nitro

attashe74 [19]

Answer:

2.29 g of N2

Explanation:

We have to start with the chemical reaction:

$NaN_3~->~Na~+~N_2$

The next step is to balance the reaction:

$2NaN_3~->~2Na~+~3N_2$

We can continue with the mol calculation using the molar mass of

$NaN_3$ (65 g/mol), so:

$3.55~g~NaN_3\frac{1~mol~NaN_3}{65~g~NaN_3}=0.054~mol~NaN_3$

Now, with the molar ratio between $NaN_3$ and $N_2$ we can calculate the moles of $N_2$ (2:3), so:

$0.054~mol~NaN_3\frac{3~mol~N_2}{2~mol~NaN_3}=0.0819~mol~N_2$

With the molar mass of $N_2$ we can calculate the grams:

$0.0819~mol~N_2=\frac{1~mol~N_2}{28~g~N_2}=2.29~g~N_2$

I hope it helps!

5 0

3 years ago

A method used by the U.S. Environmental Protection Agency (EPA) for determining the concentration of ozone in air is to pass the

baherus [9]

Answer: 1. $9.08\times 10^{-6}$ moles

2. 90 mg

Explanation:

$O_3(g)+2NaI(aq)+H_2O(l) \rightarrow O_2(g)+I_2(s)+2NaOH(aq)$

According to stoichiometry:

1 mole of ozone is removed by 2 moles of sodium iodide.

Thus $4.54 \times 10^{-6}$ moles of ozone is removed by = $\frac{2}{1}\times 4.54 \times 10^{-6}=9.08\times 10^{-6}$ moles of sodium iodide.

Thus $9.08\times 10^{-6}$ moles of sodium iodide are needed to remove $4.54\times 10^{-6}$ moles of $O_3$

2. $\text{Number of moles of ozone}=\frac{0.01331g}{48g/mol}=0.0003moles$

According to stoichiometry:

1 mole of ozone is removed by 2 moles of sodium iodide.

Thus 0.0003 moles of ozone is removed by = $\frac{2}{1}\times 0.0003=0.0006$ moles of sodium iodide.

Mass of sodium iodide= $moles\times {\text {molar mass}}=0.0006\times 150g/mol=0.09g=90mg$ (1g=1000mg)

Thus 90 mg of sodium iodide are needed to remove 13.31 mg of $O_3$ .

3 0

2 years ago