Use the information provided in appendix to answer the following questions:
a) Calculate the Kb of Acetate ion
b) Calculate the pKa of the anilinium ion (C6H5NH3+)
c) Calculate the Kb of NO2-
d) Calculate the pKb of the benzoate ion
In: Chemistry
A certain weak acid, HA, has a Ka value of 2.0×10−7.
Part A: Calculate the percent ionization of HA in a 0.10 M solution.
Part B: Calculate the percent ionization of HA in a 0.010 M solution.
In: Chemistry
Calculate the standard heat of reaction for the dehydrogenation of cyclohexane to benzene in the vapor phase.
C6H12 = C6H6 + 3 H2
The reactor for this system operates at 70% conversion of cyclohexane. If the feed rate is 4000 kg of pure C6H12 per hour at 100oC, determine the rate of heat addition to or removal from the reactor that is required if the product gases leave the reactor at 300oC.
In: Chemistry
When a 1.50 g sample of aluminum metal is burned in an oxygen atmosphere, 2.83 g of aluminum oxide are produced. However, the combustion of 1.50 g ultrafine aluminum in air results in 2.70 g of a product, which is a mixture of 80% aluminum oxide and 20% aluminum nitride (% by mass). Use this information to determine the empirical formulas of aluminum oxide and luminum nitride.
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A 75 watt incandescent light bulb and an 18 watt compact fluorescent bulb are equally bright. How much warmer will an insulated closed 12 by 11 by 8.0 foot room get in 1.0 hour if it is lighted by an incandescent bulb than if it is lighted by a fluorescent bulb? At room temperature, the specific heat of air is 1.007 J/gC and its density is 1.2 g/L. The watt is the SI unit of power; 1 watt = 1 J/s.
In: Chemistry
1) A bottling plant has 1.26521×105 bottles with a capacity of 355 mL , 1.08937×105 caps, and 4.8740×104 L of beverage.
-How many bottles can be filled and capped, how many bottles left over, how much beverage left over, how many caps left over?
2) Hydrogen gas reacts with nitrogen gas to produce ammonia
3H2(g)+N2(g)→2NH3(g)
-What is the theoretical yield in grams and percent yield for this reaction?
3) Methane (CH4 ) burns and reacts with oxygen gas to produce carbon dioxide and water
CH4(g)+2O2(g)→CO2(g)+2H2O(g)
-What is the mass of carbon dioxide, water, and oxygen from this complete combustion of 1.40*10^-3 g of methane?
Reviewing for test using online appliction, application keeps rejecting answers, some of these concepts I thought I understood well I am struggling with these problems, first one seems simple but I am missing something big thank you in advance.
In: Chemistry
thanks
Fe+3 + SCN-
---->
<----
FeSCN+2
You mix the following:
Volume of KSCN solution 4.27 mL
Original concentration of KSCN solution 0.00495 M
Volume of ferric ion solution 4.74 mL
Original concentration of ferric ion solution 0.02488 M
Voluume of distilled water 5.25 mL
You measure the %T of the blank and sample at 447 nm using the same
cuvet. Only FeSCN2+ absorbs at 446 nm! KSCN and Fe+3 are
transparent.
%T of blank 100.6
%T of sample 42.7
constant [Molarity FeSCN2+ per absorbance] 0.001264 M/A
Note: This constant is only for this pre-lab
Calculate:
a) Millimoles of SCN- originally put in solution _______________
mmoles
b) Millimoles of Fe+3 originally put in solution _______________
mmoles
c) Total volume of solution _______________ mL
d) Molarity of FeSCN2+ at equilibrium _______________ M
e) Millimoles of FeSCN2+ at equilibrium _______________
mmoles
f) Molarity of SCN- at equilibrium _______________ M
g) Molarity of Fe+3 at equilibrium _______________ M
h) Calculated equilibrium constant _______________
In: Chemistry
Using the Michaelis-Menten equation, derive an expression that will determine Km as a function or in terms of Vmax, V0 and [S]. With this derived equation then calculate:
a) Km
B) Indicate at each substrate concnetration whether this Km changes with the changing S
C) Using the double reciprocal plot, determine Km.
In: Chemistry
Nickel metal reacts with sulfuric acid in a redox reaction. In an experiment, 1.25g of nickel reacted with 55.0ml od 0.110M sulfuric acid. Hydrogen gas was collected in a 150.0ml container. The reaction takes place at 20 degrees C. One product of the reaction contained nickel (IV) ion.
a. When the reaction is complete, what will be the pressure of the gas in the container?
b. How many grams of the excess reactant will remain?
In: Chemistry
2. Which of the following statements is true (explain
why)?
a. A sample of oxygen gas at 273K will have a higher urms than a
sample of oxygen at 1000K
b. A sample of hydrogen gas at 273K will have more molecules that
are able to achieve a a speed of 2000m/s than a sample of oxygen
gas at 1000K (number of moles remaining constant)
c. A sample of hydrogen gas at 273K will have a higher urms than a
sample of the same gas at 1000K
d. None of these statements are true
e. All of these statements are true
3. Which of the following statements regarding energy entering a
system is false (explain why)?
a. Energy cannot enter or leave a system from the surroundings in
the case of an isolated system
b. Both heat (q) and work (w) would require a positive sign
c. Heat (q) would require a negative sign, while work (w) would
require a positive sign
d. All of these statements are true
e. All of these statements are false
4. Recall that the internal energy of a system is a state
function and depends only on temperature. In the isothermal
expansion of an ideal gas, which of the following statements are
true (explain why)?
a. The gas absorbs energy from its surroundings
b. The gas does work
c. The change in internal energy remains constant
d. Only a and b are true
e. All of these statements are true
5. The electron configuration for Ge is [Ar] (3d^10)(4s^2)(4p^2) What is the maximum number of electrons that can have an ml value equal to 0 (show the calculations)?
a. 8
b. 15
c. 16
d. 32
In: Chemistry
Half-reaction E° (V) Br2(l) + 2e- 2Br-(aq) 1.080V
Sn2+(aq) + 2e- Sn(s) -0.140V
Al3+(aq) + 3e- Al(s) -1.660V
(1) The weakest oxidizing agent is: enter formula (2) The strongest reducing agent is: (3) The strongest oxidizing agent is: (4) The weakest reducing agent is: (5) Will Al(s) reduce Br2(l) to Br-(aq)? (6) Which species can be oxidized by Sn2+(aq)? If none, leave box blank.
In: Chemistry
20 microliters of 1% H2O2 (weight by volume) was added to 2980 microliters of water to make 3000 microliters of solution.
(a) What is the concentration of H2O2 for this scenario?
(b) What is the concentration of H2O2 if 60 microliters of 1% H2O2 was added to 2940 microliters water?
(c) What is the concentration of H2O2 if 100 microliters of 1% H2O2 was added to 2900 microliters water?
Please show your work so I can replicate them in other similar situations, thank you.
In: Chemistry
Decide which of the following statements are true and which are false.
1. Real gas molecules behave most ideally at high temperature and low pressure.
2. At constant temperature, the heavier the gas molecules, the larger the average velocity.
3. Ideal gas molecules have small volumes and exert weak attractive forces on one another.
4. In order for two separate 1.0 L samples of O2(g) and H2(g) to have the same average velocity, the O2(g) sample must be at a lower temperature than the H2(g) sample.
5. As temperature increases, the average kinetic energy of a sample of gas molecules decreases.
6. At constant temperature, the heavier the gas molecules, the smaller the average kinetic energy.
In: Chemistry
In: Chemistry
Propranolol is an adrenergic antagonist. Compare the structure of propranolol with noradrenaline and identify which features are similar in both molecules. Suggest why this molecule might act as an antagonist rather than an agonist.
In: Chemistry