Chemistry concepts and calculations

1) A 0.000195M solution of [FeSCN]^+2 has an aborbance of 0.725. What would be t

1) A 0.000195M solution of [FeSCN]^+2 has an aborbance of 0.725. What would be the concentration of another solution of the same complex ion whose aborbance is 0.554. Assume both …

1) A 0.0641 M solution was prepared by dissolving copper wire (AW = 63.546) in n

1) A 0.0641 M solution was prepared by dissolving copper wire (AW = 63.546) in nitric acid and diluting to volume in a 100mL volumetric flask with distilled water. What was the ma…

1) A 0.100 mole quantity of a monoprotic acid HA is added to1.00 L of pure water

1) A 0.100 mole quantity of a monoprotic acid HA is added to1.00 L of pure water. When equilibrium is reached, the pH ofthe solution is 3.75. What is the value of Ka for theacid H…

1) A 0.1475M solution of Ba(OH)2 was used to titrate the acetic acid (C2H4O2=60.

1) A 0.1475M solution of Ba(OH)2 was used to titrate the acetic acid (C2H4O2=60.05) in a dilute sample. The results are tabulated below. 2C2H4O2+Ba(OH)2=Ba(C2H3O2)+2H2O sample Sam…

1) A 0.1475M solution of Ba(OH)2 was used to titrate the acetic acid (C2H4O2=60.

1) A 0.1475M solution of Ba(OH)2 was used to titrate the acetic acid (C2H4O2=60.05) in a dilute sample. The results are tabulated below. 2C2H4O2+Ba(OH)2=Ba(C2H3O2)+2H2O sample Sam…

1) A 0.23 g sample of an unknown monoprotic acid is titrated with 0.11 N NaOH. 2

1) A 0.23 g sample of an unknown monoprotic acid is titrated with 0.11 N NaOH. 23.89 mL of NaOH is required to reach the equivalence point. What is the molar mass of this acid? 2)…

1) A 1.0 mL aliquot (sample) is taken from a 1.0L solution. Which of the followi

1) A 1.0 mL aliquot (sample) is taken from a 1.0L solution. Which of the following is/are true when comparing the 1.0 mL solution to the 1.0L solution? Choose all that are true. -…

1) A 1.0-L buffer solution is 0.125 M in HNO2 and 0.180 M in NaNO2. Part A Deter

1) A 1.0-L buffer solution is 0.125 M in HNO2 and 0.180 M in NaNO2. Part A Determine the concentrations of HNO2 and NaNO2 after addition of 1.5 g HCl. Express your answers using t…

1) A 1.4326 g of sample of a new compound has been analyzed and found to contain

1) A 1.4326 g of sample of a new compound has been analyzed and found to contain the following masses of elements, carbon, 0.7263 g; hydrogen, 0.08127 g; nitrogen, 0.1412 g; oxyge…

1) A 100.0-g sample of water at 27.0 o C is poured into a 76.2-g sample of water

1) A 100.0-g sample of water at 27.0oC is poured into a 76.2-g sample of water at 89.0oC. What will be the final temperature of the water? 2) A calorimeter contains 240 g of water…

1) A 100.0-mL buffer solution is 0.175 M in HClO and 0.150 M in NaClO. Part A: W

1) A 100.0-mL buffer solution is 0.175 M in HClO and 0.150 M in NaClO. Part A: What is the initial pH of this solution? Part B: What is the pH after addition of 150.0 mg of HBr? P…

1) A 15% solution of sodium hypochlorite (NaOCl), a 75%-pure granular calcium hy

1) A 15% solution of sodium hypochlorite (NaOCl), a 75%-pure granular calcium hypochlorite [Ca(OCl)2] , and pure chlorine gas (Cl2) are each available to be used as the primary di…

1) A 15.0ML solution of 0.500 M hydrofluoric acid (HF-Ka = 7.2*10 -4 ) is titrat

1) A 15.0ML solution of 0.500 M hydrofluoric acid (HF-Ka = 7.2*10-4) is titrated with a 0.250 M solution of NaOH. Calculate the pH of the solution after the addition of the volume…

1) A 15.1 mL sample of a 0.446 M aqueous hypochlorous acid solution is titrated

1) A 15.1 mL sample of a 0.446 M aqueous hypochlorous acid solution is titrated with a 0.397 M aqueous potassium hydroxide solution. What is the pH at the start of the titration, …

1) A 18.0 L sample of hydrogen gas has a pressure of 25.0 atm. What volume would

1) A 18.0 L sample of hydrogen gas has a pressure of 25.0 atm. What volume would this gas occupy at 9.30 atm? 2) A balloon filled with helium has a volume of 20.5 L at 309 K. What…

1) A 200.0 ML solution of 1.3 x 10 -3M AgNO3 is mixed with 100mL of a 4.5 x 10-5

1) A 200.0 ML solution of 1.3 x 10 -3M AgNO3 is mixed with 100mL of a 4.5 x 10-5M Na2S solution. Assume that both of these are completely soluble. Given Ksp for AgS(s) = 1.6x10^-4…

1) A 21.30 mL volume of 0.0975 M NaOH was used to titrate 25.0 mL of a weak mono

1) A 21.30 mL volume of 0.0975 M NaOH was used to titrate 25.0 mL of a weak monoprotic acid solution to the stoichiometric point. Determine the molar concentration of the weak aci…

1) A 25.0 g sample of CO 2 is placed in an 8.00 L steel tank. What is the pressu

1) A 25.0 g sample of CO2 is placed in an 8.00 L steel tank.   What is the pressure in torr in the tank at 45oC? 2) At what temperature in oC would 25.0 g of NH3 in a 27 L steel t…

1) A 25.0 mL sample of 0.150 M hydrocyanic acid is tritated with a 0.150 M NaOH

1) A 25.0 mL sample of 0.150 M hydrocyanic acid is tritated with a 0.150 M NaOH solution. What is the pH before any base is added? The Ka of hydrocyanic acid = 4.9×10^-10 2) A 25.…

1) A 25.0 mL sample of a .290 M solution of aqueous trimethylamine is titrated w

1) A 25.0 mL sample of a .290 M solution of aqueous trimethylamine is titrated with a .363 M solution of HCl. Calculate the pH of the solution a) after 10.0 mL of acid have been a…

1) A 280. g aluminum engine part at an initial temperature of 26.0 A 280. g alum

1) A 280. g aluminum engine part at an initial temperature of 26.0 A 280. g aluminum engine part at an initial temperature of 26.0 degree C absorbs 4.58 kJ of heat. What is the fi…

1) A 3.15 x10^-6 M solution of an iodine solution was measured in a 1.00 cm cell

1) A 3.15 x10^-6 M solution of an iodine solution was measured in a 1.00 cm cell to have an absorbance of 0.267 at 635 nm. A blank solution in this cell had an absorbance of 0.019…

1) A 4.00L flask contains 2.33g of helium at 1520 mm Hg. What is the temperture

1) A 4.00L flask contains 2.33g of helium at 1520 mm Hg.  What is the temperture of the gas? Show all work a)24.3K b)41.8K c)127K d)167 e)1.27x105K 2) A flask is filled with 70.0g…

1) A 42.0 mL sample of 0.108 M HNO2 is titrated with 0.258 M KOH. (Ka for HNO2 i

1) A 42.0 mL sample of 0.108 M HNO2 is titrated with 0.258 M KOH. (Ka for HNO2 is 4.57×104.) Determine the pH at the equivalence point for the titration of HNO2 and KOH. 2) Two 27…

1) A 45.9g sample of metal is heated to 95.5 Degrees Celsius and then placed in

1) A 45.9g sample of metal is heated to 95.5 Degrees Celsius and then placed in a calorimeter containing 120.0 g of water (c=4.18 J/g`C) at 21.6 degrees celcius. The final tempera…

1) A 50.0 gram sample of water is heated from 21.5 degrees C to 26.21 degrees C.

1) A 50.0 gram sample of water is heated from 21.5 degrees C to 26.21 degrees C. How many Joules of heat were added to this solution? 2) A 15.25 gram sample of copper initially at…

1) A 50.0 gram sample of water is heated from 21.5 o C to 26.21 o C. How many Jo

1) A 50.0 gram sample of water is heated from 21.5 oC to 26.21 oC. How many Joules of heat were added to this solution? 2) A 15.25 gram sample of copper initially at 92 degrees is…

1) A 60.0 mL sample of 0.18 M HClO 4 is titrated with 0.27 M LiOH. Determine the

1) A 60.0 mL sample of 0.18 M HClO4 is titrated with 0.27 M LiOH. Determine the pH of the solution before the addition of any LiOH. -> [H+] = 0.18 --> pH = -log[H+] ---> …

1) A 75.0mL sample of water is heated to its boiling point. How much heat (in kJ

1)A 75.0mL sample of water is heated to its boiling point. How much heat (in kJ) is required to vaporize it? (Assume a density of 1.00 g/mL.)? 2)The density of an unknown metal is…

1) A 9.395 mol sample of xenon gas is maintained in a 0.7940 L container at 300.

1) A 9.395 mol sample of xenon gas is maintained in a 0.7940 L container at 300.8 K. What is the pressure in atm calculated using the van der Waals' equation for Xe gas under thes…

1) A Cu-Ni alloy with 26 wt%Ni (the balance is wt%Cu) is slowly cooled from 1500

1) A Cu-Ni alloy with 26 wt%Ni (the balance is wt%Cu) is slowly cooled from 1500oC to a temperature at which the first solid starts to form. Using the magnified section of the Cu-…

1) A Cu-Ni alloy with 26 wt%Ni (the balance is wt%Cu) is slowly cooled from 1500

1) A Cu-Ni alloy with 26 wt%Ni (the balance is wt%Cu) is slowly cooled from 1500oC to a temperature at which the first solid starts to form. Using the magnified section of the Cu-…

1) A Cu/Cu2+ concentration cell has a voltage of 0.21 V at 25 C. The concentrati

1) A Cu/Cu2+ concentration cell has a voltage of 0.21 V at 25 C. The concentration of Cu2+ in one of the half-cells is 1.5×103 M . What is the concentration of Cu2+ in the other h…

1) A For NO2, write an equation that shows how the anion acts as a base. Express

1) A For NO2, write an equation that shows how the anion acts as a base. Express your answer as a chemical equation. Identify all of the phases in your answer. B For ClO2, write a…

1) A What is the pH after 0.150 mol of HCl is added to the buffer from Part A? A

1) A What is the pH after 0.150 mol of HCl is added to the buffer from Part A? Assume no volume change on the addition of the acid. Express the pH numerically to three decimal pla…

1) A balanced chemical equation for the oxidation of oxalic acid using potassium

1) A balanced chemical equation for the oxidation of oxalic acid using potassium permanganate the oxidizing agent, in an acid solution. This reaction can be presented as a equatio…

1) A ball is projected horizontally with speed 16.7 m/s from the top of a 18.1 m

1) A ball is projected horizontally with speed 16.7 m/s from the top of a 18.1 m high building. Neglecting drag, what is its horizontal distance (in m) from the bottom of the buil…

1) A balloon containing 1.75 miles if He gas has a volume of 0.500L at a given t

1) A balloon containing 1.75 miles if He gas has a volume of 0.500L at a given temperature and pressure. If balloon loses some amount of helium gas without changing temperature an…

1) A block of copper of unknown mass has an initial temperature of 70.0 C . The

1) A block of copper of unknown mass has an initial temperature of 70.0 C . The copper is immersed in a beaker containing 91.1g of water at 22.6 C . When the two substances reach …

1) A buffer solution contains 0.329 M NH 4 Cl and 0.482 M NH 3 ( ammonia ). Dete

1) A buffer solution contains 0.329 M NH4Cl and 0.482 M NH3 (ammonia). Determine the pH change when 0.130 mol HNO3 is added to 1.00 L of the buffer. pH after addition ? pH before …

1) A buffer solution contains 0.356 M ammonium chloride and 0.396 M ammonia . If

1) A buffer solution contains 0.356 M ammonium chloride and 0.396 M ammonia. If 0.0550 moles of hydroiodic acid are added to 250 ml of this buffer, what is the pH of the resulting…

1) A buffer system contains 0.24 M NH4+ and 0.12 M NH3. p K a of NH4+ is 9.25 Ho

1) A buffer system contains 0.24 M NH4+ and 0.12 M NH3. pKa of NH4+ is 9.25 How many moles of NaOH must be added to 1.00 L of this solution to increase the pH to 9.2? 2) Titration…

1) A calibration curve for CuSO4 at 655 nm yields a straight line described by t

1) A calibration curve for CuSO4 at 655 nm yields a straight line described by the equation y = 2.821 x + 0.673. If the measured absorbance for a solution of unknown concentration…

1) A calorimeter contains 35.0 mL of water at 12.5 C . When 1.20 g of X (a subst

1) A calorimeter contains 35.0 mL of water at 12.5 C . When 1.20 g of X (a substance with a molar mass of 43.0 g/mol ) is added, it dissolves via the reaction X(s)+H2O(l)X(aq) and…

1) A carbohydrate present in the blood is: A) glucose. B) fructose. C) sucrose.

1) A carbohydrate present in the blood is: A) glucose. B) fructose. C) sucrose. D) maltose 2) A component of lactose is the sugar: A) deoxyribose. B) fructose    C) galactose D) r…

1) A carbohydrate sample weighing 0.235 g was found to have a fuel value of 3.84

1) A carbohydrate sample weighing 0.235 g was found to have a fuel value of 3.84 kJ. What is the fuel value of one gram of this carbohydrate, in nutritional Calories? A) 3,910 Cal…

1) A carbon atom double bonded to an oxygen atom and also single bonded to anoth

1) A carbon atom double bonded to an oxygen atom and also single bonded to another atom, which in turn is bonded to a hydrogen atom, is what kind of functional group? a) amine gro…

1) A certain element consists of two stable isotopes. The first has a mass of 68

1) A certain element consists of two stable isotopes. The first has a mass of 68.9 amu and a percent natural abundance of 60.4 %. The second has a mass of 70.9 amu and a percent n…

1) A chemist working in a pharmaceutical lab synthesized a new drug as a racemic

1) A chemist working in a pharmaceutical lab synthesized a new drug as a racemic mixture. Why is it important that they separate the two enantiometers and test each for its biolog…

1) A coin slides over a frictionless plane and across an xy coordinate system fr

1) A coin slides over a frictionless plane and across an xy coordinate system from the origin to a point with xy coordinates (1.90 m, 7.70 m) while a constant force acts on it. Th…