Chemistry homework questions

BountyQuestion
$1.00Past due Calculate the mass percent of salicylic acid in the recovered sample. A student performed the Separation by Fractional Crystallization experiment described with the following results: Initial mass of sample mixture: 10.95g, mass of salicylic acid recovered, 2.76g; mass of CuSO4•5H2O recovered, 4.95g. The recovered CuSO4•5H2O was then heated for 20 minutes at 120°C. The mass of the new hydrate was 3.61g. (The molar mass of H2O = 18.015 g/mol, and the molar mass of CuSO4= 159.61g/mol) Calculate the mass percent of salicylic acid in the recovered sample.
Chemistry > General Chemistry
$1.00Past due Sodium fluoride is added to many municpal water supplies to reduce tooth decay. Calculate the pH of a 0.00339 M solution Sodium fluoride is added to many municpal water supplies to reduce tooth decay. Calculate the pH of a 0.00339 M solution
Chemistry > General Chemistry
$1.00Past due General Chemistry If 14.0 ml of a 0.160 M NaOH solution are required to neutralize 11.0 ml of a sulfuric acid solution, what is the concentration of H2SO4 solution ( hint; mole ratio of H2SO4 to NaOH is 1:2 in the acid and base reaction)?
Chemistry > General Chemistry
$1.00Past due CHEMISTRY, Gas Laws - Q about Volume A 650.0 mL sample has a mass of 1.71 g at 100.0 C and 100 kPa. Calculate its molar mass.
Chemistry > General Chemistry
$1.00Past due chemistry general chemistry Compare the stability of the Zr atom and the Zr ion. Account for any differences in their stability.
Chemistry > General Chemistry
$1.00Past due Consider the titration of 50.0 mL of 0.200 M HOCl by 0.200 M KOH for the next five questions (Ka for HOCl = 3.5 x 10-8). Question is in the attachment. Thank you
Chemistry > Organic Chemistry
$1.00Past due Titrations How many milliliters of a .250 M sulfuric acid solution would be required to completely react 2.398 grams of aluminum hydroxide?
Chemistry > General Chemistry
$200.00Past due Concentration NiCl3 is a strong electrolyte. Determine the concentration of each of the individual ions in a 0.450 M NiCl3 solution.
Chemistry > General Chemistry
$1.00Past due Gen Chem Chapter 12 Question (Solutions) Methanol, CH3OH, is a compound that is used in car windshield washer fluid to lower the freezing point of the solution. If an aqueous solution of windshield washer fluid has a mole fraction of methanol of 0.520, what is the mass percentage of water in the solution?
Chemistry > General Chemistry
$1.00Past due molar mass of a volatile liquid, pre - laboratory question 1. The vapor from an unknown volatile liquid occupies a269 mL Erlenmeyer flask at 98.7C and 748 Torr. The mass of the capor is0.791g. a. How many moles of vapor are present? b. What is the molar mass of the volatile liquid? c. What is the density of the vapor at STPconditions?
Chemistry > General Chemistry
$3.00Past due Determining the formula of an unknown compound An unknown metal M reacts with Sulphur to form a compound with the formula M2S3, if 3.12g of M reacts with 2.88g of sulphur, what are the names of M and M2S3
Chemistry > Inorganic Chemistry
$1.00Past due help!!please . (S)-5,5-dibromo-3-fluoro-2-methyl-3-hexanol 2. (R)-5,5-dibromo-3-fluoro-2-methyl-3-hexanol
Chemistry > Organic Chemistry
$1.00Past due organic chem lab 1. If the crystals obtained in question (1) are recrystallized from 100 mL of solvent, what will be the yield and composition of the crystals obtained? 2. A student dissolves 80 mg of a crude product in 4.5 mL (the minimum required) of methanol at 25 °C. She cools the solution in an ice bath and obtains crystals. The crystals are recovered by filtration and rinsed with 0.5 mL of ice-cold methanol. After drying, the weight of the crystals is 5 mg. Why was the recovery so poor? What could she do...
Chemistry > Organic Chemistry
$1.50Past due chemistry help needed Phenol red is an indicator that changes color over a range from pH=6.4 to pH=8.0. What is Ka of phenol red?
Chemistry > General Chemistry
$4.50Past due Using the values for the resonance energies of benzene and naphthalene given above, explain why Diels-Alder reactions o Using the values for the resonance energies of benzene and naphthalene given above, explain why Diels-Alder reactions of anthracene take place at the center ring, not one of the end rings.
Chemistry > Organic Chemistry
$1.00Past due show how to prepare the following compounds starting from the appropriate aldehyde How we can solve this kind of question
Chemistry > Organic Chemistry
$1.00Past due chem question Rank the following acids in order of weakest to strongest acid. CH3CH2COOH, CF3CH2CH2CH2OH, H2SO3, CH2BrCH2COOH. a 519 ml sample of HClO4 has a pH of .3172 if 553 ml of distilled water was added to the HClO4 solution what would the new pH of the solution be? A 315 ml sample of 1.1451 M HBr is mixed with 521 ml sample o KOH (which has a pH of 13.48) What is the pH of the resulting solution?
Chemistry > General Chemistry
$1.00Past due Calculation of Kp Kp=2.26×104 at 298 K Calculate Kp for the reaction below. 3CH3OH(g)⇌3CO(g)+6H2(g)
Chemistry > General Chemistry
$25.00Past due CHM/110 Chemical Reaction Paper Select one of the following products that utilizes a chemical reaction as a main feature: Cold pack Hot pack Can of food that cooks when opened Light sticks Epoxy glue Commercially available antacids Baking soda and lemon juice Bleach Note. If you want to select another product that utilizes a chemical reaction, you must obtain facilitator approval prior to beginning this assignment. Prepare a 350- to 700-word paper in which you examine how your product utilizes a chemical reaction as a main feature. Include...
Chemistry > General Chemistry
$1.00Past due Excercise 1.128 Lead metal can be extracted from a mineral called galena, which contains 86.6% lead by mass. A particular ore contains 68.5% galena by mass. If the lead can be extracted with 92.5% efficiency, what mass of ore is required to make a lead sphere with a 4.00 cm radius?
Chemistry > General Chemistry
$1.00Past due List the ionic formula There are about 7 cation that need to orginzed to solved this problem.. I tried so many time but each time it is saying it wrong List the ionic formula for all of the cations you will be working with in this experiment in alphabetical order by name, separated by commas. Include charges, putting the number before the sign of the charge (2+ or 1-). Example: Magnesium would be Mn2+, with no spaces between any of the characters. Ag,Pb,Ni,Mn,Fe,NH4, and Al
Chemistry > Materials Chemistry
$5.50Past due Review of related literature and studies Purifying used cooking oil, please give me some of related studies and literature about this study.
Chemistry > Biochemistry
$32.00Past due Arizona State - assignment $32 Arizona State - assignment $32 thanks
Chemistry > General Chemistry
$8.00Past due ASU Reply, thanks please view attachment ASU Reply, thanks please view attachment.
Chemistry > General Chemistry
$4.00Past due Chemistry Question: Metal Crystals The substance beta manganese is found to crystallize in a cubic lattice, with an edge length of 630.0 pm. If the density of solid beta manganese is 7.297 g/cm3, how many Mn atoms are there per unit cell?
Chemistry > General Chemistry
$1.00Past due General Chemistry Carbonyl fluoride, COF2, is an important intermediate used in the production of fluorine-containing compounds. For instance, it is used to make the refrigerant carbon tetrafluoride, CF4 via the reaction 2COF2(g)⇌CO2(g)+CF4(g), Kc=6.40 If only COF2 is present initially at a concentration of 2.00 M, what concentration of COF2 remains at equilibrium?
Chemistry > General Chemistry
$1.00Past due Chemistry Question Write the formulas of the three singly chlorinated isomers formed when 2,2-dimethylbutane reacts with Cl2 in the presence of light.
Chemistry > General Chemistry
$1.00Past due basic Chemistry Consider the reaction : Mg(s) + 2 HCl(aq)  MgCl2(aq) + H2(g) What minimum amount of 1.85 M HCl (in L) is required to produce 28.5 L of H2 at STP?
Chemistry > General Chemistry
$1.00Past due Basic Chemistry How much of a 5.0 M sucrose solution should you use to make 85.0 mL of a 0.050 M solution?
Chemistry > General Chemistry
$1.00Past due Basic Chemistry A KNO3 solution is made using 88.4 g of KNO3 and diluted to a total solution volume of 1.50 L. Calculate the molarity and the mass percent of solution (assume a density of 1.05 g/mL of solution).
Chemistry > General Chemistry