1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
vovangra [49]
3 years ago
12

Determine the pH at the equivalence point for the titration of 40.0 mL of 0.1 M HNO2 by 0.200 M KOH (Example 16.7). (The pKa of

nitrous acid is 3.36.)
Chemistry
1 answer:
Fynjy0 [20]3 years ago
8 0

Answer:

pH=13.28

Explanation:

Nitrous acid

HNO_2 \longrightarrow H^+ + NO_2^-

Ka=\frac{[H^+][NO_2^-]}{[HNO_2]}

pKa=-log(Ka)=3.36

Ka=4.36*10^{-4}

<u>Balance: </u>

[H^+]=X

[NO_2^-]=X

[HNO_2]=0.1-X

Ka=\frac{X*X}{0.1-X}

4.36*10^{-4}=\frac{X^2}{0.1-X}

4.36*10^{-5}-4.36*10^{-4}*X=X^2

Solving:

X=6.4*10^{-3}

The NaOH is in excess:

[NaOH]_f=0.2-0.0064=0.1936

pH=14+log([OH^-])

pH=14+log(0.1936)=13.28

You might be interested in
After severe dust storms in the 1930s, practices were put in place to reduce soil erosion. Which
timurjin [86]

Answer: Farmers were paid to practice soil-conserving techniques like crop rotation and terracing

Explanation:

read about it here: https://www.pbs.org/wgbh/americanexperience/features/dust-bowl-surviving-dust-bowl/

5 0
3 years ago
Read 2 more answers
What is the metric unit for mass?<br> a.Meters<br> b.Kilograms<br> c.Pounds<br> d.matter
fiasKO [112]
The metric unit for mass is B. Kilograms
7 0
3 years ago
CALCULATOR
suter [353]

Answer: The possible molecular formula will be CO_2

Explanation:

Mass of C= 27.3 g

Mass of O = 72.7 g

Step 1 : convert given masses into moles.

Moles of C =\frac{\text{ given mass of C}}{\text{ molar mass of C}}= \frac{27.3g}{12g/mole}=2.275moles

Moles of O =\frac{\text{ given mass of O}}{\text{ molar mass of O}}= \frac{72.7g}{16g/mole}=4.544moles

Step 2 : For the mole ratio, divide each value of moles by the smallest number of moles calculated.

For C = \frac{2.275}{2.275}=1

For O =\frac{4.544}{2.275}=2

The ratio of C : O = 1: 2

Hence the empirical formula is CO_2

The possible molecular formula will be=n\times CO_2

5 0
3 years ago
Omg GUYS I NEED HELPPP
Ilia_Sergeevich [38]

27) Partial pressure of oxygen: 57.8 kPa

29) Final volume: 80 mL

30) Final volume: 8987 L

31) Due to property of water of being polar, ice floats on water

Explanation:

27)

In a mixture of gases, the total pressure of the mixture is the sum of the partial pressures:

p_T = p_1 + p_2 + ... + p_N

In this problem, the mixture contains 3 gases (helium, carbon dioxide and oxygen). We know that the total pressure is

p_T=201.4 kPa

We also know the partial pressures of helium and carbon dioxide:

P_{He}=125.4 kPa\\P_{CO_2}=18.2 kPa

The total pressure can be written as

p_T=p_{He}+p_{CO_2}+p_{O_2}

where p_{O_2} is the partial pressure of oxygen. Therefore, we find

p_{O_2}=p_T-p_{He}-p_{CO_2}=201.4-125.4-18.2=57.8 kPa

29)

Assuming that the pressure of the gas is constant, we can apply Charle's law, which states that:

"For an ideal gas at constant pressure, the volume of the gas is proportional to its absolute temperature"

Mathematically,

\frac{V}{T}=const.

where

V is the volume of the gas

T is the Kelvin temperature

We can re-write it as

\frac{V_1}{T_1}=\frac{V_2}{T_2}

Here we have:

V_1 = 42 mL (initial volume)

T_1=-89^{\circ}C+273=184 K is the initial temperature

T_2=77^{\circ}C+273=350 K is the final temperature

Solving for V2, we find the final volume:

V_2=\frac{V_1 T_2}{T_1}=\frac{(42)(350)}{184}=80 mL

30)

For this problem, we can use the equation of state for ideal gases, which can be written as

\frac{p_1 V_1}{T_1}=\frac{p_2 V_2}{T_2}

where in this problem:

p_1 = 102.3 kPa is the initial pressure

V_1=1975 L is the initial volume

T_1=25^{\circ}C+273=298 K is the initial temperature

p_2=21.5 kPa is the final pressure

T_2=12^{\circ}C+273=285 K is the final temperature

And solving for V2, we find the final volume of the balloon:

V_2=\frac{p_1 V_1 T_2}{p_2 T_1}=\frac{(102.3)(1975)(285)}{(21.5)(298)}=8987 L

31)

A molecule of water consists of two atoms hydrogen bond with an atom of oxygen (H_2 O) in a covalent bond.

While the molecul of water is overall neutral, due to the higher electronegativity of the oxygen atom, electrons are slightly shifted towards the oxygen atom; as a result, there is a slightly positive charge on the hydrogen side, and a slightly negative charge on the oxygen side (so, the molecules is said to be polar).

As a consequence, molecules of water attract each other, forming the so-called "hydrogen bonds".

One direct consequence of the polarity of water is that ice floats on liquid water.

Normally, for every substance on Earth, the solid state is more dense than the liquid state. However, this is not true for water, because ice is less dense than liquid water.

This is due to the polarity of water. In fact, when the temperature of water is decreased to freezing point and water becomes ice, the hydrogen bondings "force" the molecules to arrange in a lattice structure, so that the molecules become more spaced when they turn into solid state. As a result, ice occupies more volume than water, and therefore it is less dense, being able to float on water.

Learn more about ideal gases:

brainly.com/question/9321544

brainly.com/question/7316997

brainly.com/question/3658563

#LearnwithBrainly

4 0
3 years ago
How is nuclear energy generated?
balandron [24]
Nuclear power plants heat water to produce steam. The steam is used to spin large turbines that generate electricity. ... In nuclear fission, atoms are split apart to form smaller atoms, releasing energy. Fission takes place inside the reactor of a nuclear power plant.
3 0
3 years ago
Read 2 more answers
Other questions:
  • (Timed) What part of an atom involved in a chemical reaction?
    10·1 answer
  • How many grams of calcium would be a typical amount in a 60-kg adult?
    15·2 answers
  • How much heat is evolved in converting 1.00 mol of steam at 155.0 ∘c to ice at -50.0 ∘c? the heat capacity of steam is 2.01 j/(g
    9·1 answer
  • An iron block of mass 18 kg is heated from 285 K to 318 K. If 267.3 kJ is required, what is the specific heat of iron? A. 450.00
    5·1 answer
  • Consider the decomposition of a metal oxide to its elements where m represents a generic metal. m3o4
    5·1 answer
  • Select the correct layer.<br> In which layer is lithification most likely to occur?
    12·1 answer
  • What is the scaling factor if the molar mass of
    7·1 answer
  • HI! I REALLY NEED HELP, THANK YOU!!
    14·1 answer
  • My labmate discovered a new compound and wanted to try to determine what it could be. We noticed that when mixed with an acid, i
    8·1 answer
  • What did ancient Indians create using metallurgy?<br> texts<br> plows<br> sitars<br> paintings
    9·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!