All categories

3 years ago

The consentration of a solution can be changed by _____ solute

Chemistry

1 answer:

Ghella [55]3 years ago

4 0

The concentration of a solution can be changed by adding solute. More solute=more concentrated

You might be interested in

Z u need help with this assignment

dmitriy555 [2]

Answer:

Explanation:

Get a better image plz

5 0

3 years ago

Read 2 more answers

A diprotic acid, H₂A, has Ka1 = 3.4 × 10⁻⁴ and Ka2 = 6.7 × 10⁻⁹. What is the pH of a 0.18 M solution of H₂A?

Tcecarenko [31]

Answer:

pH = 2.10

Explanation:

We name an acid as diprotic because it can release two protons:

H₂A + H₂O ⇄ H₃O⁺ + HA⁻ Ka₁

HA⁻ + H₂O ⇄ H₃O⁺ + A⁻² Ka₂

We propose the mass balance:

Analytical concentration = [H₂A] + [HA⁻] + [A⁻²]

As Ka₂ is so small, we avoid the [A⁻²] so:

0.18 M = [H₂A] + [HA⁻]

But we can not avoid the HA⁻, because the Ka₁. Ka₁'s expression is:

Ka₁ = [H₃O⁺] . [HA⁻] / [H₂A]

We propose the charge balance:

[H₃O⁺] = [HA⁻] + [A⁻²] + [OH⁻]

As we did not consider the A⁻², we can miss the term and if

Kw = H⁺ . OH⁻

We replace Kw/H⁺ = OH⁻. So the new equation is:

[H₃O⁺] = [HA⁻] + Kw / [H₃O⁺]

The acid is so concentrated, so we can avoid the term with the Kw, so:

[H₃O⁺] = [HA⁻]

In the mass balance we would have:

0.18 M = [H₂A]

We replace at Ka₁

Ka₁ = [H₃O⁺] . [HA⁻] / [H₂A]

Ka1 . 0.18 / [H₃O⁺] = [HA⁻]

We replace at the charge balance:

[H₃O⁺] = Ka1 . 0.18 / [H₃O⁺]

[H₃O⁺]² = 3.4×10⁻⁴ . 0.18

[H₃O⁺] = √(3.4×10⁻⁴ . 0.18)

[H₃O⁺] = 7.82×10⁻³

- log [H₃O⁺] = pH → - log 7.82×10⁻³

pH = 2.10

5 0

3 years ago

PLEASE ANSWER CORRECTLY !!!!!!!!!!!!!! WILL MARK BRAINLIEST !!!!!!!!!!!!!!

geniusboy [140]

Answer:

the ice has reached its melting point

the water has reached its freezing point

the whatever that is has reached its cooling point I guess

8 0

3 years ago

Read 2 more answers

The volume of a bubble that starts at the bottom of a lake at 4.55°C increases by a factor of 8.00 as it rises to the surface wh

Masja [62]

Answer:

The depth of the lake is 67.164 meters.

Explanation:

The combined gas equation is,

$\frac{P_1V_1}{T_1}=\frac{P_2V_2}{T_2}$

where,

$P_1$ = initial pressure of gas in bubble= ?

$P_2$ = final pressure of gas = 0.980 atm

$V_1$ = initial volume of gas = $V$

$V_2$ = final volume of gas = 8.00 × V

$T_1$ = initial temperature of gas = $4.55^oC=273.15+4.55=277.7 K$

$T_2$ = final temperature of gas = $18.05^oC=273.15+18.05=291.2 K$

Now put all the given values in the above equation, we get:

$\frac{P_1\times V}{277.7 K}=\frac{0.980 atm\times 8.00\times V}{291.2 K}$

$P_1=7.476 atm$

pressure of the gas in bubble initially is equal to the sum of final pressure and pressure exerted by water at depth h.

$P_1=P_2+h\rho\times g$

Where :

$\rho =$ density of water = $1.00 g /cm^3=1000 g/m^3$

g = acceleration due gravity = $9.8 m/s^2$

$7.476 atm=0.980 atm +h\rho\times g$

$6.496 atm=h\rho\times g$

$6.496 \times 101325 Pa=h\1000 g/m^3\times 9.8 m/s^2$

h = 67.164 m

The depth of the lake is 67.164 meters.

4 0

3 years ago

What are the building blocks of starch molecules

murzikaleks [220]

Answer:

Glucose is the building block for starch

Explanation:

(amylose and amylopectin)

8 0

3 years ago