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How do we turn petroleum into energy we use?

arlik [135]

You don't "turn" it into energy; petroleum HAS stored energy (chemical energy).However, you can turn it into ANOTHER TYPE OF ENERGY; usually this is done by burning the petroleum, and using it to drive machinery.

Since burning fuels is wasteful (the efficiency is limited, in theory, to the Carnot efficiency of a heat engine), other options are being explored, such as chemical reactions in a fuel cell. But such technology is not yet used on a large scale.

7 0

3 years ago

Calculate the solubility of CaF2 in g/L (Ksp = 4.0 x 10-8). 2. What is the pH of a solution containing a hydrogen ion concentrat

Pepsi [2]

Answer:

$\large \boxed{1. \text{ 0.17 g/L; 2. 3.52; 3. Cl; 4. (a) +3; (b) +4; (c) +6}}$

Explanation:

1. Solubility of CaF_2

(a) Molar solubility

CaF₂ ⇌ Ca²⁺ + 2F⁻

$K_{\text{sp }} = \text{[Ca$^{2+}$]}\text{[F$^{-}$]}^{2}= 4.0 \times 10^{-8}\\s(2s)^{2}=4.0 \times 10^{-8}\\4s^{3} = 4.0 \times 10^{-8}\\s^{3} = 1.0 \times 10^{-8}\\s =2.2 \times 10^{-3}\text{ mol/L}$

(b) Mass solubility

$\text{Solubility} = 2.2 \times 10^{-3} \text{ mol/L} \times \dfrac{\text{78.07 g}}{\text{1 L }} = \text{0.17 g/L}\\\\\text{The solubility of CaF$_{2}$ is $\large \boxed{\textbf{0.17 g/L}}$}$

2. pH

pH = -log [H⁺] = -log(3.0 × 10⁻⁴) = 3.52

3. Oxidizing and reducing agents

Zn + Cl₂ ⟶ ZnCl₂

$\rm \stackrel{\hbox{0}}{\hbox{Zn}} + \stackrel{\hbox{0}}{\hbox{ Cl}_{2} }\longrightarrow \stackrel{\hbox{+2}}{\hbox{Zn}}\stackrel{\hbox{-1}}{\hbox{Cl}_{2}}$

The oxidation number of Cl has decreased from 0 to -1.

Cl has been reduced, so Cl is the oxidizing agent.

4. Oxidation numbers

(a) Al₂O₃

$\stackrel{\hbox{$\mathbf{+3}$}}{\hbox{Al}_{2}}\stackrel{\hbox{-2}}{\hbox{O}_{3}}$

1O = -2; 3O = -6; 2Al = +6; 1Al = +3

(b) XeF₄

$\stackrel{\hbox{$\mathbf{+4}$}}{\hbox{Xe}}\stackrel{\hbox{-1}}{\hbox{F}_{4}}$

1F = -1; 4F = -4; 1 Xe = +4

(c) K₂Cr₂O₇

$\stackrel{\hbox{${+1}$}}{\hbox{K}_{2}}\stackrel{\hbox{$\mathbf{+6}$}}{\hbox{Cr}_{2}}\stackrel{\hbox{-2}}{\hbox{O}_{7}}$

1K = +1; 2K = +2; 1O = -2; 7O = -14

+2 - 14 = -12

2Cr = + 12; 1 Cr = +6

8 0

3 years ago

HELPPPPP ME <br><br>PLISSSSS

Talja [164]

Answer:

pH value of a solution depends on the concentration of hydrogen ions

(pH = -log[H+(aq)].

Hydrochloric acid is a strong acid, while ethanoic acid is a weak acid. Strong acids ionize completely in water (to give ions which includes H+(aq)), while weak acids only ionize partially in water.

Therefore, even if both hydrochloric acid and ethanoic acid are monobasic acids (each molecule can ionize completely to give 1 hydrogen ion), since hydrochloric acid ionizes completely in water and ethanoic acid does not ionize completely, the concentration of hydrogen ions in hydrochloric acid is higher than that of ethanoic acid, leading to a lower pH value for hydrochloric acid, while higher for ethanoic acid.

8 0

3 years ago

Suppose that, from measurements in a microscope, you determine that a certain layer of graphene covers an area of 1.50μm2. Conve

Alex73 [517]

The answer is 1.5*10^-12 square meters. For a detailed calculation, please refer to the attachment.

Download docx

7 0

3 years ago

If a proton and an electron are released when they are 5.50×10−10 mm apart (typical atomic distances), find the initial accelera

Vlada [557]

Answer: The initial acceleration of the proton = (4.56 × 10^23) m/s2

The initial acceleration of the electron = (8.36 × 10^26) m/s2

Explanation: The force of attraction between the proton and electron can be computed using the statements of Coulomb's law which state that the force of attraction between two charged particles is directly proportional to the product of the two charges and inversely proportional to the square of their distances apart.

F = (Kq1q2)/(r^2) where K = (9 × (10^9) Nm(C^-2))

But q1 is the charge on a proton = (1.6 × (10^-19)) C

q2 is charge on an electron = -(1.6 × (10^-19)) C

r = (5.50 × (10^-10))mm = (5.50 × (10^-13))m

Computing all that, F = 0.0007616529 N = (7.62 × 10^-4) N

But the force of attraction is converted to that required for motion when they're released.

F = ma.

For proton, m = (1.67 × 10^-27) kg

a = F/m = 0.000762/(1.67 × 10^-27) = (4.56 × 10^23) m/s2

For electron, m = (9.11 × 10^-31) kg

a = F/m = 0.000762/(9.11 × 10^-31) = (8.36 × 10^26) m/s2

QED!

7 0

2 years ago