answer.
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
Rainbow [258]
2 years ago
12

In the Acid-Base Chemistry Experiment the measurement of pH will be used to explore acid-base concepts, analyze an unknown, and

determine percent K and Fe in the iron salt. The pH is measured using pH paper, acid-base indicators, and a combination pH electrode. Quantitative measurements are made using a combination pH electrode interfaced with a computer in a pH titration using dilute NaOH. The molarity of a strong acid (HCl), equivalent weight and pKa of an unknown weak acid, and percent K and Fe in your iron salt are all determined in this way. Samples of the iron salt are run through a cation exchange column to prepare for titration. Choose either True or False for each of the following statements : A solution with a hydronium molarity of 0.00045 is acidic. pH is a way to express the hydronium concentration over a wide range.Percent K and Fe are determined by doing ion exchange then a pH titration.About 0.2M HCl is the titrant used for the pH titrations. A Lewis base is a species that can donate a proton to an acid
Chemistry
1 answer:
aleksley [76]2 years ago
5 0

Answer

a)  A solution with a hydronium molarity of 0.00045 is acidic. True

Doing the calculus of pH

pH= -Log [H^{+}] = -Log (0.00045)

b) pH is a way to express the hydronium concentration over a wide range. True

pH means –Log[H+] and this value is used to express a wide range of hydronium concentration sometimes obtaining pH minor than zero.

c) Percent K and Fe are determined by doing ion exchange then a pH titration. False

Usually, Fe is determined by redox titration with potassium permanganate due to it’s more accurate. On the other hand, K is determined usually by volumetric process which includes precipitation like potassium picrate precipitate

d) About 0.2M HCl is the reagent used for the pH titrations. False.

In order to do pH titration, it is possible to use a wide range of HCl concentrations and other acids as reagent if the analyte is a basic compound. Otherwise, if the analyte is an acid compound you should use a basic compound as reagent.

e) A Lewis base is specie that can donate a proton to an acid. False

A Lewis base is an electron pair donor.

You might be interested in
Avanti works in a bookstore. She has four books and is going to place them in two stacks. The diagram above shows the books befo
Feliz [49]

Answer:

Well they didn't transfer any energy when they weren’t touching and it did t produce any energy if it didn’t move. Since they are on top of each other they are causing momentum on each other creating kinetic energy

Explanation:

3 0
1 year ago
An amount of solid barium chloride, 20.8 g, is dissolved in 100 g water in a coffee-cup calorimeter by the reaction: BaCl2 (s) 
mamaluj [8]

Answer : The enthalpy change during the reaction is -6.48 kJ/mole

Explanation :

First we have to calculate the heat gained by the reaction.

q=m\times c\times (T_{final}-T_{initial})

where,

q = heat gained = ?

m = mass of water = 100 g

c = specific heat = 4.04J/g^oC

T_{final} = final temperature = 26.6^oC

T_{initial} = initial temperature = 25.0^oC

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

q=100g\times 4.04J/g^oC\times (26.6-25.0)^oC

q=646.4J

Now we have to calculate the enthalpy change during the reaction.

\Delta H=-\frac{q}{n}

where,

\Delta H = enthalpy change = ?

q = heat gained = 23.4 kJ

n = number of moles barium chloride = \frac{\text{Mass of barium chloride}}{\text{Molar mass of barium chloride}}=\frac{20.8g}{208.23g/mol}=0.0998mole

\Delta H=-\frac{646.4J}{0.0998mole}=-6476.95J/mole=-6.48kJ/mole

Therefore, the enthalpy change during the reaction is -6.48 kJ/mole

8 0
2 years ago
For a school event 1/6 of the athletic field is reversed for the fifth -grade classes the reserved part of the field is divided
SVETLANKA909090 [29]

Answer:

\frac{1}{24}

Explanation:

Given:

For a school event, 1/6 of the athletic field is reserved for the fifth -grade classes and the reserved part of the field is divided equally among the 4 fifth grade classes in the school.

To find: fraction of the whole athletic field reserved for each fifth class

Solution:

Fraction of the whole athletic field reserved for four fifth classes = \frac{1}{6}

So, fraction of the whole athletic field reserved for each fifth class = \frac{1}{4}(\frac{1}{6})=\frac{1}{24}

3 0
2 years ago
A researcher claims that an ancient scroll originated from greek scholars in about 500 bce. a measure of its carbon-14 decay rat
Naddik [55]
The amount of substance present in a certain object with a given half-life in terms of h can be expressed through the equation,

     A(t) = (A(o))(0.5)^(t/h)

where A(t) is the amount of substance after t years and A(o) is the original amount. In this item we are given that A(t)/A(o) is equal to 0.89. Substituting the known values,

     0.89 = (0.5)(t / 5730 years)

The value of t from the equation is 963.34 years.

<em>Answer: 963 years</em>
8 0
2 years ago
What is the kinetic energy acquired by the electron in hydrogen atom, if it absorbs a light radiation of energy 1.08x101 J. (A)
Delvig [45]

Explanation:

The given data is as follows.

            Energy of radiation absorbed by the electron in hydrogen atom = 1.08 \times 10^{-17} J

As energy is absorbed as a photon. Hence, frequency will be calculated will be as follows.

                                    E = h \nu

               1.08 \times 10^{-17} J = 6.626 \times 10^{-34} Js \times \nu

               \nu = 0.163 \times 10^{17} s^{-1}

or,                \nu = 1.63 \times 10^{16} s^{-1}    

It is known that,        \nu = \frac{c}{\lambda}

                1.63 \times 10^{16} s^{-1} = \frac{3 \times 10^{8} m/s}{\lambda}                  

                   \lambda = 1.84 \times 10^{-8} m

And, according to De-Broglie equation \lambda = \frac{h}{p}

as,        p = m \times \nu

So,          \lambda = \frac{h}{m \times \nu}

            m \times \nu = \frac{6.626 \times 10^{-34} Js}{1.84 \times 10^{-8} m}          

                             = 3.6 \times 10^{-26} J/m

Now, on squaring both the sides we get the following.

           (m \times \nu)^{2} = (3.6 \times 10^{-26} J/m)^{2}    

                              = 12.96 \times 10^{-52}  

               m \times \nu^{2} = \frac{12.96 \times 10^{-52}}{m}

where,   m = mass of electron

So,           m \times \nu^{2} = \frac{12.96 \times 10^{-52}}{m}

                             = \frac{12.96 \times 10^{-52}}{9.1 \times 10^{-31}}

                                   = 1.42 \times 10^{-21} J

Since,  K.E = \frac{1}{2}m \nu^{2}

                 = \frac{1.42 \times 10^{-21} J}{2}

                 = 0.71 \times 10^{-21} J

Thus, we can conclude that kinetic energy acquired by the electron in hydrogen atom is 7.1 \times 10^{-22} J.

4 0
2 years ago
Other questions:
  • The forces between water molecules are stronger than the forces between ethanol molecules. Which liquid would probably be most d
    12·2 answers
  • Convert mass to moles for both reactants. (round to 2 significant figures.) 2.50 g cuci2 equals moles e 0.25 g Al equals moles D
    5·2 answers
  • Consider the equation: 2NO2(g) N2O4(g). Using ONLY the information given by the equation which of the following changes would in
    15·2 answers
  • Calculate the number of carbon atoms in 25.0 grams of isopropyl alcohol (c3h8o)
    5·2 answers
  • What is the oxidation state of an individual bromine atom in kbro2?
    6·1 answer
  • 5. Given the cell notation Cu(s)|Cu2+(aq)||Ag+(aq)|Ag(s), what is the half-reaction that occurs at the anode?
    5·2 answers
  • After a reaction, a new compound contains 0.73 g Mg and 0.28 g N. What is the empirical formula of this compound?
    12·1 answer
  • A solution contains one or more of the following ions: Ag + , Ca 2 + , and Co 2 + . Ag+, Ca2+, and Co2+. Lithium bromide is adde
    11·1 answer
  • the image above shows a chamber with a fixed volume filled with gas at a pressure of 1560 mmHg and a temperature of 445.0 K. If
    11·1 answer
  • An experimenter studying the oxidation of fatty acids in extracts of liver found that when palmitate (16:0) was provided as subs
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!