At 1 atm, how much energy is required to heat 49.0 g of H2O(s) at –10.0 °C to H2O(g) at 119.0 °C?

Technetium-99 is used as a radioisotope in a variety of medical applications . if a patient receives a dosage of 6.00 mg at 8 am on thursday , then how much would remain at 4pm on friday afternoon? the half life of Tc-99 is 6.0 hours.

What are the benefits and drawbacks in CZE (Capillary Zone Electrophoresis) with other more conventional separation technique, such as HPLC (High Performance Liquid Chromatography)?

A buffer solution was prepared by dissolving 4.00 grams of sodium propanate (NaCH3CH2CO2, FM 96.06 g/mol) in a solution containing 0.100 moles of propanoic acid (CH3CH2CO2H) and diluting the mixture to 1.00 L. pKa for propanoic acid is 4.874.

(a) To this solution was added 5.00mL of 1.00 M HCl. Calculate the pH of the resulting solution.

(b) To this solution was added 5.00mL of 1.00 M NaOH. Calculate the pH of the resulting solution.

can someone please give me name, structure and percebtage of FAME that are likely produces from the vegetable oil? i need 3! and it has to be similar to the fatty acid structure of vegetable oil!

Use the Henderson–Hasselbalch equation to calculate the pH of each solution:

Part A

a solution that is 16.5 g of HF and 22.0 g of NaF in 125 mL of solution

Part B

a solution that contains 1.23% C2H5NH2 by mass and 1.30% C2H5NH3Br by mass

Part C

a solution that is 15.0 g of HC2H3O2 and 15.0 g of NaC2H3O2 in 150.0 mL of solution

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Starting with a ccp array of anions, what structure types are generated by a) filling all tetrahedral sites with cations, b) filling half of the tetrahedral sites, e.g. T₊, with cations c) filling all octahedral sites with cations and d) filling alternate layers of octahedral sites with cations? Comment on the absence of any known structure type in one of these four categories.

Deep water fish are hard to transport to the surface safely. Why do you think that is?

As the water pressure decreases, there is not enough oxygen for the fish in the water

As the water pressure increase, the air in the swim bladder compresses until they burst.

As the water pressure decreases,the air in the swim bladder compresses until they burst. Is it this one... and explain why or why not

As the water pressure decreases,the air in the swim bladder expand. until they burst.

The Determination of Magnesium by Direct Titration

Preparation of Solutions:

Buffer solution, pH 10: Diluted 57mL of NH₃ and 7g NH₄Cl totaling 100mL solution

Eriochrome Black T: Dissolved 102.4mg in 15mL ethanolamine and 5mL of absolute ethanol

EDTA: 3.8008g of purified dihydrate Na₂H₂Y 2H₂O, mixed with distilled water to total volume of 1L

I received a Magnesium Sulfate unknown, and diluted it to 500mL with distilled water then transferred 3 50mL aliquots to separate conical flasks and added 2mL of pH10 buffer and 4 drops of Eriochrome Black T to each flask and titrated each with 0,01M EDTA until I reached the endpoint. My 1st resulted in 19.23mL of EDTA used, 2nd 19.26mL EDTA and 3rd was 19.25mL EDTA used.

During this, I was not given the weight of the unknown Magnesium Sulfate. I am confused on how to determine the unknown Magnesium Sulfate, and express the results as ppm of Mg²⁺ in the unknown sample.

What salt is produced in each of the following neutralization reactions?

HNO3(aq)+KOH(aq)→H2O(l)+?

HNO3(aq)+Ca(OH)2(aq)→H2O(l)+?

HCl(aq)+Ca(OH)2(aq)→H2O(l)+?

HCl(aq)+KOH(aq)→H2O(l)+?

Drag the appropriate items to their respective reaction. K2NO3, KNO3, Ca(NO3)2, CaNO3, CaCl, CaCl2,

KCl2, KCl

Reaction A-

Reaction B-

Reaction C-

Reaction D –

Not a product -

Consider the following portion of the energy-level diagram for hydrogen:

In the hydrogen spectrum, what is the wavelength of light associated with the n = 2 to n = 1 electron transition? Please explain. The answer is: 1.22 × 10^–7 m.

Hi! Can someone summarize what the reaction article is saying? I am having trouble understanding it.

The purpose of this experiment was to investigate the catalytic performance of solid acid catalyst developed from modification of coal combustion fly ash to synthesize methyl 4-aminobenzoate (MAB) by Fischer esterification between 4-aminobenzoic acid and methanol. Upon acid modification of fly ash, surface acidity of solid acid catalyst (SAC) is greatly enhanced as a result of increased surface area, augmented silica content, and fabricated phosphates. The proposed mechanism, similar to our lab, demonstrates that the surface acid sites of solid acid catalyst (SAC) initiate the reaction by donating proton to 4-aminobenzoic acid, resulting in the formation of carbocation, which is then attacked by the electron-rich oxygen atom of methanol. Subsequent loss of water and deprotonation resulted in the formation of the desired product, MAB. Recyclability study reveals that the solid acid catalyst (SAC) retains similar catalytic activity till the fifth reaction cycle furnishing the yield of methyl 4-aminobenzoate in the range 82–98% This unveils that the acidity remains unaffected during regeneration of the catalyst. This eco-friendly, highly efficient, and low-cost solid acid catalyst system may be used as a replacement of harmful traditional liquid acids for important reactions in pharmaceutical industries to synthesize indispensable drugs.