Chemistry

On another planet, the isotopes of titanium have the given natural abundances. Isotope Abundance Mass (u) 46Ti 70.600% 45.95263 48Ti 11.900% 47.94795 50Ti 17.500% 49.94479 What is the average atomic mass of titanium on that planet? average atomic mass = 47.867
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Which of the following is true about a municipal bond with a put option? (A) An investor will exercise the option to put the bond if yields rise significantly. (B) An investor must have the issuer's permission to put the bond. (C) The market price of bonds is never affected by a put option feature. (D) Yields are usually higher for a new issue bond with a put option than for a new issue bond without a put option.
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The half-life of a radioactive isotope is the amount of time it takes for a quantity of radioactive material to decay to one-half of its original amount.
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Draw the partial (valence-level) orbital diagram, and write the symbol, group number, and period number of the element:(a) [Ne] 3s3p(b) [Ar] 4s3d4p
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A. After the label fell off a bottle containing a clear liquid believed to be benzene, a chemist measured the density of the liquid to verify its identity. A 25.0-mL portion of the liquid had a mass of 21.95 gg. A chemistry handbook lists the density of benzene at 15CC as 0.878 g/mg/mL. Is the calculated density in agreement with the tabulated value? B. An experiment requires 15.0 g of cyclohexane, whose density at 25oC is 0.7781 g/mL. What volume of cyclohexane should be used?C. A spherical ball of lead has a diameter of 5.0 cm. What is the mass of the sphere if lead has a density of 11.34 g/cm3?
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A sample of uranium ore contains 6.73 mg of 238U and 3.22 mg of 206Pb. Assuming all of the lead arose from the decay of the uranium and that the half-life of 238U is 4.51 x 109years, determine the age of the ore
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g The decomposition reaction of A to B is a first-order reaction with a half-life of 2.42103 seconds: A 2B If the initial concentration of A is 0.163 M, how many minutes will it take for the concentration of A to be 66.8% of the initial concentration?
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Nitrogen dioxide (NO2) cannot be obtained in a pure form in the gas phase because it exists as a mixture of NO2 and N2O4. At 26C and 0.80 atm, the density of this gas mixture is 2.2 gL1. What is the partial pressure of each gas?
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Naturally occurring iodine has an atomic mass of 126.9045 amu. A 12.3849-g sample of iodine is accidentally contaminated with 1.00070 g of 129I, a synthetic radioisotope of iodine used in the treatment of certain diseases of the thyroid gland. The mass of 129I is 128.9050 amu. Find the apparent "atomic mass" of the contaminated iodine.
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What is the normal boiling point of etanoic acid?
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Increasing the amount of water in which the sugar is dissolved will increase the frequency of collisions between the sucrose molecules and the water molecules resulting in an increase in the rate of hydrolysis.True or false?
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Chlorine can be prepared in the laboratory by the reaction of manganese dioxide with hydrochloric acid, HCl(aq)HCl(aq), as described by the chemical equationMnO2(s)+4HCl(aq)MnCl2(aq)+2H2O(l)+Cl2(g)MnO2(s)+4HCl(aq)MnCl2(aq)+2H2O(l)+Cl2(g)How much MnO2(s)MnO2(s) should be added to excess HCl(aq)HCl(aq) to obtain 115 mL Cl2(g)115 mL Cl2(g) at 25 C and 805 Torr805 Torr?
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Citrus fruits are rich in citric acid, a compound with three COOH groups. Explain the following: a. The first pKa (for the COOH group in the center of the molecule) is lower than the pKa of acetic acid. b. The third pKa is greater than the pKa of acetic acid.
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The volume of 1 kg of helium in a piston-cylinder device is initially 5 m3 . Now helium is compressed to 2 m3 while its pressure is maintained constant at 180 kPa. Determine the work required to compress helium, in kJ.
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The observed rotation of 2.0 g of a compound in 50 mL of solution in a polarimeter tube 20 cm long is +138. What is the specific rotation of the compound?
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A sample of helium gas initially at 37.0C, 785 torr and 2.00 L was heated to 58.0C while the volume expanded to 3.24 L. What is the final pressure in atm?
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2 PointsWhich of the following is true of tetrads?THEREMENTELEOSDELETELESERIESSEDEROA. They exist throughout the process of meiosis.OB. They separate during meiosis I.EHEEEEESERIESOLEHCHILEBENZHEERUHERAPIEmegetBRISHIELETEENIER02HERRERAFERIEESTECDENTERESEBRERCSBARTHHARFFREE FORFSHASELTERRGENESISESSFREEOC. They are found only in haploid cells.OD. They also form in cells undergoing mitosis.THE NEHEFREEMEF
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In nature, the element X consists of two naturally occurring isotopes. 107X with abundance 53.84% and isotopic mass 106.9051 amu and 109X with isotopic mass 108.9048 amu. Use the given information to calculate the atomic mass of the element X to an accuracy of .001% (Report your answer like this yyy.yyyy)
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which sequence of coefficients should be placed in the blanks to balance this equation
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How do the physical and chemical properties of the element change?
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The percent copper in an unknown copper compound is 21.90 %. What is the formula weight of the unknown compound? You may assume that one mole of the compound contains one mole of copper. Enter your answer in units of amu.
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One reason carbon monoxide (CO) is toxic is that it binds to the blood protein hemoglobin more strongly than oxygen does. The bond between hemoglobin and CO absorbs radiation of 1953 cm . (The units are the reciprocal of the wavelength in centimeters.) Calculate the wavelength (in nm and ) and the frequency (in Hz) of the absorbed radiation.
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if you begin with 210.3 g of Cl2, how many grams of HCl will you end up with? CH4 + 3Cl2 CHCl3 + 3HCl *
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Write the appropriate symbol for each of the following isotopes: (a) Z = 19, A = 41 (b) Z = 46, A = 106 (c) Z = 52, A = 125 (d) Z = 38, A = 88
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