What is the reason for heat transfer from one substance to another?

Calculate the pH and fraction of dissociation ( α ) for each of the acetic acid ( CH 3 COOH , p K a = 4.756 ) solutions. A 0.002

marysya [2.9K]

Answer:

The degree of dissociation of acetic acid is 0.08448.

The pH of the solution is 3.72.

Explanation:

The $pK_a=4.756$

The value of the dissociation constant = $K_a$

$pK_a=-\log[K_a]$

$K_a=10^{-4.756}=1.754\times 10^{-5}$

Initial concentration of the acetic acid = [HAc] =c = 0.00225

Degree of dissociation = α

$HAc\rightleftharpoons H^++Ac^-$

Initially

c

At equilibrium ;

(c-cα) cα cα

The expression of dissociation constant is given as:

$K_a=\frac{[H^+][Ac^-]}{[HAc]}$

$1.754\times 10^{-5}=\frac{c\times \alpha \times c\times \alpha}{(c-c\alpha)}$

$1.754\times 10^{-5}=\frac{c\alpha ^2}{(1-\alpha)}$

$1.754\times 10^{-5}=\frac{0.00225 \alpha ^2}{(1-\alpha)}$

Solving for α:

α = 0.08448

The degree of dissociation of acetic acid is 0.08448.

$[H^+]=c\alpha = 0.00225M\times 0.08448=0.0001901 M$

The pH of the solution ;

$pH=-\log[H^+]$

$=-\log[0.0001901 M]=3.72$

3 0

3 years ago

Write the charge and full ground-state electron configuration of the monatomic ion most likely to be formed by each:

Sladkaya [172]

Answer:

Part A:

Charge is $P^{3-}$

Configuration is $1s^2 2s^22p^63s^23p^6$

Part B:

Charge is $Mg^{2+}$

Configuration is $1s^2 2s^22p^6$

Part C:

Charge is $Se^{2-}$

Configuration is $1s^2 2s^22p^63s^23p^64s^23d^{10}4p^6$

Explanation:

Monatomic ions:

These ions consist of only one atom. If they have more than one atom then they are poly atomic ions.

Examples of Mono Atomic ions: $Na^+, Cl^-, Ca^2^+$

Part A:

For P:

Phosphorous (P) has 15 electrons so it require 3 more electrons to stabilize itself.

Charge is $P^{3-}$

Full ground-state electron configuration of the mono atomic ion:

$1s^2 2s^22p^63s^23p^6$

Part B:

For Mg:

Magnesium (Mg) has 12 electrons so it requires 2 electrons to lose to achieve stable configuration.

Charge is $Mg^{2+}$

Full ground-state electron configuration of the mono atomic ion:

$1s^2 2s^22p^6$

Part C:

For Se:

Selenium (Se) has 34 electrons and requires two electrons to be stable.

Charge is $Se^{2-}$

Full ground-state electron configuration of the mono atomic ion:

$1s^2 2s^22p^63s^23p^64s^23d^{10}4p^6$

8 0

3 years ago

Name this compound <br><br> please helppp thank you!!!

SSSSS [86.1K]

Answer:

Sodium sulfide is the chemical compound with the formula Na 2 S, or more commonly its hydrate Na 2 S·9H 2 O. Both are colorless water-soluble salts that give strongly alkaline solutions. When exposed to moist air, Na 2 S and its hydrates emit hydrogen sulfide , which smells like rotten eggs.

I'm not sure if it's right but it's a guess because of the 2Na.

8 0

3 years ago

Read 2 more answers

9.03g of magnesium combine completely with 4.30g of nitrogen

Readme [11.4K]

it is 12.51 grams cause u just add them together

5 0

3 years ago

A block has a mass of 325g and a volume of 500mL. What is its density? If water has a density (D=m/v) of 1g/mL, will the block f

Licemer1 [7]

Answer:

A. 0.65g/mL, float

Explanation:

Mass: 325g

Volume: 500mL

D = m/v

D = 325/500

D = 0.65

Therefore, the block has a density of 0.65g/mL and it will float since the density of water is greater than the density of the block.

4 0

4 years ago