In: Chemistry
Ammonia, NH3, and oxygen can be reacted together in the presence of a catalyst to form only nitrogen monoxide and water. The number of moles of oxygen consumed for every 9.00 moles of NO produced is :
In: Chemistry
sodium bicarbonate 10 g sodium carbonate 12.72 g, add-50 ml of deionized water to the beaker and stir until all of the weak acid or weak base has dissolved. Carefully and slowly pour the weak acid or weak base solution into the volumetric flask.
preparation of Buffer
pour your weak acid and your weak base together into a bottle.
How many grams of sodium bicarbonate (M.W.= 84.01 g/mole) would you have had to weigh out to make up 500ml of a 0.300M solution of this weak acid?
It takes 0.500liters of 4.00 M Naoh (lye) solution to clean a drain. How many grams of Naoh would have to be weighed out?
How many grams of any solid would you need to weigh out to make 2.5L of a 4% solution? (Recall, a 4% solution means 4 g/100 mL)
You will make up 100ml of a 0.20 M solution of a weak acid, sodium bicarbonate and 100ml of a 0.20 M solution of its conjugate base, sodium carbonate.
How many grams of weak acid should be weighed out? How many grams of conjugate base should be weighed out?
Do I put acid first in the water first or base in the water first? Can you write more legibly please?
In: Chemistry
if you had used a calorimeter that was not insulated as well, how would your results be affected? what about a calorimeter that was more insulted?
In: Chemistry
Match the correct term with the description:
Terms: Metal ion indicator, acid-base indicator, auxiliary complexing agent, direct, back,
displacement, indirect, and masking agent.
Titration where anions that precipitate with metal ions can be measured. ___________
Titration where the analyte is titrated with standard EDTA. _______________
Ligand that is added to keep some component of the analyte from reacting
with EDTA. _____________
Compound that changes color when bound to a metal ion. _______________
Titration where the analyte is treated with a metal-EDTA complex. _________
Compound that has a different color for each protonated state. _______________
Ligand added to keep metal ions from forming solid hydroxides. _______________
Titration where an excess of EDTA is added to the analyte. _______________
In: Chemistry
1. A sample of methane gas that occupies a volume
of 12.8 L at a temperature of 0 °C and a pressure
of 1 atm contains ________ moles of gas.
2. A mixture of argon and helium gases, in a 9.49 L flask at 39 °C, contains 6.75 grams of argon and 1.61 grams of helium. The partial pressure of helium in the flask is _______ atm and the total pressure in the flask is _______ atm.
In: Chemistry
Calculate the enthalpy of reaction for the following reaction using Hess's Law and the equations provided below.
Target Reaction: Sr(s)+C(graphite)+1 1/2 O2(g) -----> SrCO3(s) H(degrees)=?
C(Graphite)+ O2(g)-----> CO2(g) H(degrees)= -349kJ
Sr(s)+ 1/2 O2(G)-------> SrO(s) H(degrees)= -592kJ
SrO(s)+CO2(g)-------> SrCo3(s) H(degrees)= -234kJ
In: Chemistry
If 25.0 mL of a 0.238M FeO4^2- solution is allowed to react with 55.0 mL of 1.47 M aqueous ammonia, what volume of nitrogen gas can form at 25°C and 1.50 atm?
Volume = mL
In: Chemistry
Preparation of a buffer:
Dissolve in a beaker 27.3 g NaC2H3O2·3H2O in water containing 60 mL
of 1 M HCl (you need to make a 250- mL of 1 M hydrochloric acid
solution in advance by the appropriate dilution of concentrated
HCl) and dilute with the distilled water to 1 L. Invert the bottle
up to 20 times and keep the buffer in a 1 L glass bottle.
*help with dilution of concentrated hcl
In: Chemistry
Werecertainionstypicallyalwayssolubleoralwaysinsoluble?Howcouldyoutell?Includespecificexamples.
In: Chemistry
Describe in your own words how any two types of the following types of chromatography work: adsorption, partition, ion exchange, molecular exclusion, or affinity.
In: Chemistry
What volume, in liters, of O2 measured at 760 torr and 25o C is needed to completely react with 18.47 g of iron to give Fe2O3?
In: Chemistry
Describe the major properties, methods of analysis, and clinical use of:
AFP
CA-125
CEA
Beta-hCG
PSA
In: Chemistry
a. what is the difference between a flourescence excitation spectrum and a fluorescence emission spectrum?. which resembles an absorption spectrum.
b. consider a molecule that can fluoresce from the s1 state and phosphoresce from the t1state. which is emitted at longer wavelength?make a sketch showing absorption fluorescence and phosphorescence on a single spectrum.
In: Chemistry
Azulene is a beautiful blue hydrocarbon consisting of only C and H atoms. If 0.106 g of the compound is burned in oxygen, 0.364 g of CO2 and 0.0596 g of H2O are made. Determine the empirical formula of azulene from this data. [ Hint: First convert the masses of CO2 and H2O to moles, then convert the moles found to moles of C to H. ]
In: Chemistry