The dictionary from #2 falls off the table. How much kinetic energy does it have just before it hits the floor?

consider an exceptionally weak acid, HA, with Ka= 1 x 10-20. you make 0.1M solution of the salt NA. what is the pH.

iogann1982 [59]

Answer:

$pH=10.5$

Explanation:

Hello,

In this case, the dissociation of the given weak acid is:

$HA\rightleftharpoons H^++A^-$

Therefore, the law of mass action for it turns out:

$Ka=\frac{[H^+][A^-]}{[HA]}$

That in terms of the change $x$ due to the reaction extent is:

$1x10^{-23}=\frac{x*x}{0.1-x}$

Thus, by solving with the quadratic equation or solver, we obtain:

$x=31.6x10^{-12}M$

Which clearly matches with the hydrogen concentration in the solution, therefore, the pH is:

$pH=-log(-31.6x10^{-12})\\pH=10.5$

Regards.

5 0

2 years ago

Zinc is used as a coating for steel to protect the steel from environmental corrosion. If a piece of steel is submerged in an el

sweet [91]

Answer:

A) 3.17 g of Zn

Explanation:

Let's consider the reduction of Zn(II) that occurs in an electrolysis bath.

Zn⁺²(aq) + 2e⁻ → Zn(s)

We can establish the following relations:

1 min = 60 s
1 A = 1 C/s
The charge of 1 mole of electrons is 96,468 C (Faraday's constant).
When 2 moles of electrons circulate, 1 mole of Zn is deposited.
The molar mass of Zn is 65.38 g/mol

The mass of Zn deposited under these conditions is:

$24min \times \frac{60s}{1min} \times \frac{6.5C}{s} \times \frac{1mol\ e^{-} }{96,468C} \times \frac{1molZn}{2mol\ e^{-}} \times \frac{65.38g}{1molZn} = 3.17 g$

3 0

2 years ago

The gas in an aerosol can is at a pressure of 3.16 atm at 32.2°C. What would the gas pressure in the can be at 22.9°C?

olasank [31]

Answer:

The pressure of the gas would be 3.06 atm

Explanation:

Amonton's law states that the pressure is directly proportional to the absolute temperature of a gas under constant volume. The equation is:

P1 / T1 = P2 / T2

<em>Where P1 is the initial pressure = 3.16atm</em>

<em>T1 is initial absolute temperature = 273.15 + 32.2°C = 305.35K</em>

<em>P2 is our incognite</em>

<em />

Replacing:

3.16atm / 305.35K = P2 / 296.05K

3.06 atm = P2

<h3>The pressure of the gas would be 3.06 atm</h3>

5 0

2 years ago

Why are aldehydes more reactive than ketones?

Simora [160]

Answer:

Aldehydes are typically more reactive than ketones due to the following factors. ... The carbonyl carbon in aldehydes generally has more partial positive charge than in ketones due to the electron-donating nature of alkyl groups. Aldehydes only have one e- donor group while ketones have two.

Explanation:

5 0

3 years ago

Write the Formulas for these ionic compounds:

Alinara [238K]

Answer:

<h2>1. Tin(IV) oxide</h2>

Tin(IV) oxide, also known as stannic oxide, is the inorganic compound with the formula SnO₂. The mineral form of SnO₂ is called cassiterite, and this is the main ore of tin. With many other names, this oxide of tin is an important material in tin chemistry. It is a colourless, diamagnetic, amphoteric solid.

Formula: SnO₂

Molar mass: 150.71 g/mol

Melting point: 1,630 °C

Density: 6.95 g/cm³

<h2>2. Aluminum oxide</h2>

Aluminium oxide is a chemical compound of aluminium and oxygen with the chemical formula Al₂O₃. It is the most commonly occurring of several aluminium oxides, and specifically identified as aluminium(III) oxide.

Formula: Al₂O₃

Molar mass: 101.96 g/mol

Melting point: 2,072 °C

Density: 3.95 g/cm³

Boiling point: 2,977 °C

ChemSpider ID: 14086

ChemSpider ID: 26988

<h2>3. Silver sulfide</h2>

Silver sulfide is an inorganic compound with the formula Ag ₂S. A dense black solid, it is the only sulfide of silver. It is useful as a photosensitizer in photography. It constitutes the tarnish that forms over time on silverware and other silver objects.

Formula: Ag2S

Molar mass: 247.8 g/mol

Density: 7.23 g/cm³

ChemSpider ID: 145878

<h2>4. Copper (II) sulfate</h2>

Copper(II) sulfate, also known as copper sulphate, are the inorganic compounds with the chemical formula CuSO₄ₓ, where x can range from 0 to 5. The pentahydrate is the most common form. Older names for this compound include blue vitriol, bluestone, vitriol of copper, and Roman vitriol.

Formula: CuSO4

IUPAC ID: Copper(II) sulfate

Molar mass: 159.609 g/mol

Density: 3.6 g/cm³

Melting point: 110 °C

Soluble in: Water

<h2>5. Potassium carbonate</h2>

Potassium carbonate is the inorganic compound with the formula K₂CO₃. It is a white salt, which is soluble in water. It is deliquescent, often appearing as a damp or wet solid. Potassium carbonate is mainly used in the production of soap and glass.

Formula: K2CO3

Molar mass: 138.205 g/mol

IUPAC ID: Potassium carbonate

Density: 2.43 g/cm³

Melting point: 891 °C

Soluble in: Water

Explanation:

Hope it is helpful....

4 0

2 years ago