How do GMOs relate to chemistry and everyday life? What are the pro's and con's of using GMO's/Pesticides? What are the dangers associated with their usage? Are there natural pesticides available? Do they work as well?

A. Which of the following buffer systems would be the best choice to create a buffer with pH = 9.05?
HF/KF
HNO2/KNO2
NH3/NH4Cl (correct answer)
HClO/KClO

B. For the best system, calculate the ratio of the masses of the buffer components required to make the buffer. Express your answer using two significant figures.

m(NH3)/m(NH4Cl) =

How to identify the kinetic pathway or thermodynamic pathway based on example? Show 2 or 3 examples

also, show how to determine the value from keq and delta G based on your figure.

a. (3 pts) All Brønsted-Lowry acids contain the hydrogen ion, H+ . True False

b. (3 pts) You can use any acid/conjugate base pair in making a buffer. True False

c. (3 pts) Concentration does not matter for acids/conjugate bases in buffers. True False

1) Predict the sign, (+) or (-), for ∆H and ∆S for the following reactions.

2 C(s) + O (g)         2CO(g)                                 ∆H: _____                  ∆S: _____

CO₂ (s)      CO₂ (g)                                              ∆H: _____                  ∆S: _____

N₂(g) + 3H₂(g)      2NH₃(g)                                 ∆H: _____                  ∆S: _____

2) Use the standard entropy values below to calculate the entropy change (∆S^o_rxn) for the following balanced equation. N₂ (g) + 2 O₂ (g) --> 2 NO₂ (g)

Species        S^{o , (J/K*mol)}   

N₂(g)            191.5                                

O₂(g)            205.0                                                     

NO₂(g)         240.0

3) A reaction for which ∆H and ∆S are both negative will be:     

a. spontaneous at high temperatures.

b. spontaneous at low temperatures.

c. spontaneous at all temperatures.

d. never be spontaneous

e. more information is needed to determine spontaneity.

Answers I got: 1) - + , + - , + - 2) -121.5 3) I think its A.

Thanks

1. What is the change in pH when 10.0 mL of 0.010 M HCl is added to 500 mL of pure water.

2. What is the change in pH when 10.0 mL of 0.010 M NaOH is added to 500 mL of pure water.

1- brilliant colors in fireworks are due to electrons within the colorant chemicals

a) mixing with water in the atmosphere

b) reacting with the ozone layer

c) falling back to the ground state

2- the electron of an atom that play an important part in the formation of compounds are usually those

a) the d subshell

b) an incomplete inner (inside) enegy level

c) a complete inner (inside) enegy level

d) a complete outer enegy level

e) an incomplete outer enegy level

3- what type(s) of intermolecular forces are present in ethanol? CH3 CH2 OH

a) London Dispersion forces

b) Hydrogen Bonding

c) Ionic bonding

d) Dipole-Dipole interaction

e) London Dispersion forces, Dipole-Dipole interaction & Hydrogen Bonding.

If the endpoint in a titration was reached using a volume of 37.60 mL and the concentration of the standard NaOH solution was 0.3214 M, how many grams of KHP were neutralized in this experiment? (MM of KHP = 204.23 g/mol)

Report your answer in grams but do not include units in your response.

please answer the following questions by typing, thanks.

1. How different is the measured volume from the volume if it had been obtained under STP conditions? Is the difference greater than an assumed measurement error of 5%? If not, why should we go to all this trouble to make this calculation?

2. All gases should have the same standard volume of 22.4141 L. If your value is different, then comment on the sources of error in the experiment.

3. What is the volume occupied by 11 moles of oxygen gas at STP?

4. What is the mass in grams of 10.0 L of methane (CH4) gas at STP?

1) GC-MS of your sample will result in a total ion chromatogram and a mass spectrum. Explain the information that each contains and label the axes.

a) Total Ion Chromatogram

b)Mass Spectrum

2) Antihistamine contains one of the active ingrediants below. Draw the chemical structure and give the expected m/z for the molecular ion.

a) Cetirizine b) Loratadine c) Diphemhydramine d) Chlorphenamine

What volume of CO2(g) will be formed when 2.0 g CaCO3(s) is heated and the gas is collected at 700 mm pressure and 20 ^oC? The reaction is: CaCO3(s) → CaO(s) + CO2(g)

A. 0.44 L                     B. 0.52 L                     C. 52 L                                    D. 3.61 L                     E. 22.4 L

What is the mass of CO2 in a 340. mL container when its pressure is 2.80 atm and the temperature is 57 ^oC?

A. 26.7 g                     B. 0.125 g                    C. 125 g                      D. 3.52 g                     E. 3.47x10^–4 g

Briefly discuss any source of errors in the HPLC Lab ''Liquid Chromatographic Analysis of Analgesic Powders''

•The persistent presence of O2 in the atmosphere is intimately connected with the removal of CO2 from the atm as part of the inorganic C cycle.

•What is the chemistry behind it?

•How is the geospheric cycle involved in this?

•We referred to this not as a simple cycle, but as a feedback loop. How does this feedback loop work?

Light from three different lasers (A, B, and C), each with a different wavelength, was shined on the same metal surface. Laser A produced no photoelectrons. Lasers B and C both produced photoelectrons, but those produced by B had a greater velocity than those produced by C. Arrange the lasers in order of increasing wavelength.

If A didn't produce any photoelectrons, Wouldn't it just be a straight line with the highest frequency? And to have a greater velocity would that mean the wavelength increases frequency?

Explain how solubility tests could be used to differentiate between:

a. a phenol and a carboxylic acid.

b. a phenol that contains electron-withdrawing groups and a phenol that contains electron-donating groups.

c. a carboxylic acid and an amine.

d. 1-bromooctane and dibutyl ether. e. 2-pentyne and pentane.

f. 2-nitropentane and 2-aminopentane.