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
vfiekz [6]
3 years ago
11

g Tom's roommate Bob spilled crystal violet solution on his lab coat, and Tom offers to use some lye (sodium hydroxide solution)

to clean it off. Bob suggest diluting the lye with water, but Tom argues that the cleaning action will be faster if concentrated lye is used. Bob counters that the speed of cleaning doesn't depend on the concentration of the lye. Who is correct? Use your results to support your conclusion.
Chemistry
1 answer:
irina [24]3 years ago
4 0

Answer:

Tom is correct. The rate of reaction of Crystal violet and NaOH is first order with respect to NaOH, hence, a higher concentration of NaOH corresponds to a higher rate of reaction; a faster reaction.

This means the speed of cleaning depends on the concentration of the lye used.

Explanation:

The reaction between Crystal violet and NaOH, represented as

CV⁺ + OH⁻ → CVOH

It is a reaction that is know to turn the violet colour of the crystal violet colourless.

The rate of the reaction is also known to be second order; first order with respect to Crystal violet and first order with respect to NaOH.

This means that the rate of reaction is directly proportional to the concentration of NaOH provided all other parameters such as the rate constant and the concentration of Crystal violet are constant.

Hence, the reaction becomes faster with an increased concentration of NaOH.

So, Tom is right, concentrated lye solution would remove the stain faster.

Bob is wrong.

Hope this Helps!!!

You might be interested in
chemist in South America claims to have discovered a new element with an atomic number of 34. An extremely rare element, it was
Tasya [4]

Answer:

the element he has discovered is called Selenium.

Explanation:

Selenium has an atomic number of 34

7 0
3 years ago
An equal number of moles of KI (potassium iodide) and MgI2 (magnesium iodide) are dissolved in equal volumes of water.
SOVA2 [1]
<span>  As we know that MgI2 (magnesium iodide) when dissociated it gives more ions than  the KI so it has more boiling point as its boiling point is high it means that it boils more so it has low vapor pressure and freezing point

On the other hand as we know that KI dissociates into two  ions so so it has high freezing and vapor pressure
hope it helps</span>
3 0
3 years ago
Value of Δ H ∘ rxn for the equation NH 3 ( g ) + 2 O 2 ( g ) ⟶ HNO3 ( g ) + H 2 O ( g )
koban [17]

Answer: - 894.6 kJ/mol.

Explanation:

Hess law is states that the changes in enthalpies in a chemical reactions is independent of the pathway between the initial and final states.

∆H is the change in the sum of the internal energy of a system.

We are to find the Value of ΔH°(rxn) for the equation:

NH3 (g) + 2 O2 (g) ⟶ HNO3 (g) + H2O (g). ----------------------------------(**).

From the series of equations given;

==> 4NH3 (g) + 5O2 (g) -------->4 NO(g) + 6H2O (l). ∆H = -1166.0 kJ/mol.--------------------------------------(1).

===> 2NO(g) + O2 (g) ------> 2NO2 (g). ∆H = -116.2 kJ/mol.---------------(2).

===> 3NO2 (g) + H2O (l) ---------> 2HNO3 (aq) + NO (g). ∆H = -137.3 kJ/mol.-------------------------------------(3).

The first thing to do is to multiply equation (2) by 3. Also, multiply equation (3) by 2. This will give us equation (4) and (5) respectively.

6NO + 3 O2 ----------------> 6NO2. ∆H= 3 × (-116.2 kJ/mol) = -348.6 kJ/mol. ------------------------------------(4).

6NO2 + 2 H2O ----------------> 4HNO3 + 2 NO. ∆H= 2 × (-137.3kj/mol) = -274.6 kJ/mol ---------------------------(5).

Next, add equations (4) and (5) to give;

4NO +3O2 +2H2O -------------> 4HNO3. ∆H = -623.2 kJ/mol. -----(6).

Add this equation to the equation (1) from above, we have;

4NH3 + 8O2 --------------> 4HNO3 + 4H2O. ∆H= -1789.2 kJ/mol. --------(7).

Then, divide the equation (7) above by 2 to give us back the equation (**).

NH3 (g) + 2 O2 (g) ⟶ HNO3 (g) + H2O (g). ∆H= -894.6 kJ/mol.

Δ H^∘ (rxn)= - 894.6 kJ/mol.

5 0
3 years ago
What is the resistance of a 150 W lightbulb connected to a 24 V voltage source?
Luda [366]

Answer:

3.84 Ω

Explanation:

From the question given above, the following data were obtained:

Electrical power (P) = 150 W

Voltage (V) = 24 V

Resistance (R) =?

P = IV

Recall:

V = IR

Divide both side by R

I = V/R

P = V/R × V

P = V² / R

Where:

P => Electrical power

V => Voltage

I => Current

R => Resistance

With the above formula (i.e P = V²/R), we can calculate resistance as illustrated below:

Electrical power (P) = 150 W

Voltage (V) = 24 V

Resistance (R) =?

P = V²/R

150 = 24² / R

150 = 576 / R

Cross multiply

150 × R = 576

Divide both side by 150

R = 576 / 150

R = 3.84 Ω

Thus, the resistance is 3.84 Ω

4 0
3 years ago
Find the pH of the equivalence point and the volume (mL) of 0.0372 M NaOH needed to reach the equivalence point in the titration
elixir [45]

Answer:

8.54

Explanation:

At equivalence point :  

42.2 X 0.052 = Vol. NaOH X 0.0372

Vol of NaOH = 2.1944/0.0372 = 58.99 ml

So volume of NaOH recquired to reach equivalence point = 58.99 ml

Number of miliimoles of CH3COOH = molarity X volume in ml = 42.2 X 0.052             = 2.1944 millimoles

Number of millimoles of NaOH = 58.99 X 0.0372 = 2.1944

Now CH₃COOH and NaOH reacts to give CH₃COONa according to the reaction :

CH₃COOH + NaOH ------> CH₃COONa + H₂O

1 mole of CH₃COOH reacts with 1 mole of NaOH to give 1 mole of CH₃COONa  

So 2.1944 millimoles of CH₃COOH will react with 2.1944 millimoles of NaOH to give 2.1944 millimoles of CH₃COONa

So all the acid (CH₃COOH) and base (NaOH) has been converted into salt (CH₃COONa) so there is no acid or base left.

Now molarity of CH₃COONa = number of millimoles of CH₃COONa/total volume in ml = 2.1944/(58.99 + 42.2) = 2.1944/101.19 = 0.02169 M

So using the hydrolysis equation :  

pH = 1/2 [ pKw + pKa + log c ]  

Ka for acetic acid = 1.75 X 10⁻⁵  

so pKa = -log (1.75 X 10⁻⁵) = 4.74  

Kw = 10⁻¹⁴

so pKw = -log 10⁻¹⁴ = 14

c = 0.02169  

so log c = log 0.02169 = -1.66  

putting the values....  

pH = 1/2 [14 + 4.74 - 1.66 ]  

pH = 1/2 [ 17.08] = 8.54

6 0
3 years ago
Read 2 more answers
Other questions:
  • Who am I? Most of us have characteristics of both metal and nonmetals-dull or shiny, brittle, malleable or ductile. A)Metals B)N
    14·2 answers
  • What is the molecular geometry of the underlined carbon atom in the following compound: HC-C-CH3?
    10·1 answer
  • What is the isotopic notation for phosphorus
    12·1 answer
  • A scientist compares two samples of white powder. one powder was present at the beginning of an experiment. the other powder was
    15·2 answers
  • The concentrations of Fe and K in a sample of riverwater are 0.0400 mg/kg and 1.30 mg/kg, respectively. Express the concentratio
    11·1 answer
  • Which of the following is a correct description of a double bond between two carbon atoms?
    9·2 answers
  • The following quantities were reported on the labels of commercial products. Determine the number of significant figures in each
    6·1 answer
  • 19pts please help How many grams of CO are needed to react with an excess of Fe203 to produce 225.5 g Fe? Number after the symbo
    5·1 answer
  • Can Petroleum be mixed with water?
    11·2 answers
  • Step 1: Pick your favorite physical activity This can be almost anything! Try to pick an activity that you like to participate i
    6·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!