Draw the Lewis electron dot diagram for each element. a. Krypton b. Sulfur
Draw the Lewis electron dot diagram for each substance. Double or triple bonds may be needed. a. CS2 b. NH2CONH2 (assume that the N and C atoms are the central atoms)
What is the Lewis electron dot diagram of H2S? Circle the electrons around each atom to verify that each valence shell is filled.
Draw the Lewis electron dot diagram for each substance. a. GeH4 b. ClF
How do you know which side of a polar bond has the partial positive charge? Identify the positively charged side of each polar bond. a. HCl b. NF
Which covalent bond is strongeran OO double bond or an NN double bond?
Identify the electron group geometry and the molecular geometry of each molecule. a. BI3 b. PH3
What are the Lewis electron dot diagrams of PO33 and PO43?
Each of the following statements is incorrect. Rewrite them so they are correct. a. Temperature changes during a phase change. b. The process of a liquid becoming a gas is called sublimation.
What is the difference between a gas and vapor?
Referring to Figure 10.8, at approximately what pressure is the boiling point of water 40C?
Predict the type of solid exhibited by each substance. a. Hg b. PH3 c. CaF2
A solution is made by dissolving 3.33 g of HCl(g) in 40.0 g of liquid methyl alcohol (CH3OH). Identify the solvent and solute in the resulting solution.
A solution is made by mixing 33.8 g of CH3OH in 50.0 g of H2O. What is the mole fraction of CH3OH in the solution?
A solution is made by mixing 33.8 g of C6H12O6 in 50.0 g of H2O. If the vapor pressure of pure water is 25.7 torr, what is the vapor pressure of the solution?
How many moles of MgCl2 are present in 0.0331 L of a 2.55 M solution?
For sanitary reasons, water in pools should be chlorinated to a maximum level of 3.0 ppm. In a typical 5,000 gal pool that contains 21,200 kg of water, what mass of chlorine must be added to obtain...
Chromium is thought to be an ultratrace element, with about 8.9 ng present in a human body. If the average body mass is 75.0 kg, what is the concentration of chromium in the body in pptr?
The osmotic pressure of a 0.050 M LiCl solution at 25.0C is 2.26 atm. What is the true van't Hoff factor of this ionic compound? Why is it less than the ideal value?
Write the balanced chemical equation for the neutralization reaction between H2SO4 and Cr(OH)3. What is the salt?
Na3PO4 would be product of the reaction of what acid and what base?
Identify each substance as an Arrhenius acid, an Arrhenius base, or neither. a. C6H12O6 b. HNO2 c. Ba(OH)2
Identify the conjugate acid-base pairs in this reaction. HClO3 + (C2H5)3N ( ClO3 + (C2H5)3NH+
Write the balanced chemical equation for the reaction of each acid and base pair. a. H3C5H5O7 + Mg(OH)2 b. HC3H3O3 + (CH3)3N c. HBr + Fe(OH)3
For a given aqueous solution, if [H+] = 2.07 1011 M, what is [H+]?
For a given aqueous solution, if [OH] = 7.11 1010 M, what is [H+]?
What are [H+] and [OH] in a 6.02 104 M solution of Ca(OH)2?
What is the pH of a solution when [H+] is 9.04 1013 M?
Can a buffer be made by combining a strong acid with a strong base? Why or why not?
Which combinations of compounds can make a buffer? Assume aqueous solutions. a. HCl and NaCl b. HNO2 and NaNO2 c. NH4NO3 and HNO3 d. NH4NO3 and NH3
Explain why NaBr cannot be a component in either an acidic or a basic buffer.
Write the neutralization reaction in which ZnCl2, also found in Exercise 1, is the salt product.
Citric acid (C6H8O7) is the acid found in citrus fruits. It can lose a maximum of three H+ ions in the presence of a base. Write the chemical equations for citric acid acting stepwise as a...
Write the equilibrium equation between elemental hydrogen and elemental oxygen as reactants and water as the product.
The following reaction is at equilibrium: 4HBr + O2 + 2H2O + 2Br2 If [HBr] is 0.100 M, [O2] is 0.250 M, and [H2O] is 0.0500 M at equilibrium, what is [Br2] at equilibrium if the Keq is 0.770?
The following reaction is at equilibrium: CH4 + 2C12 + CH2 C12 + 2HC1 If [CH4] is 0.250 M, [Cl2] is 0.150 M, and [CH2Cl2] is 0.175 M at equilibrium, what is [HCl] at equilibrium if the Keq is 2.30?
Given this equilibrium, predict the direction of shift for each stress. H2(g) + I2 (s) + 53 kJ + 2HI(g) a. Decreased temperature b. Increased pressure c. Removal of HI
What are [Ba2+] and [F] in a saturated solution of BaF2(s)? The Ksp of BaF2(s) is 1.8 107.
An award is being plated with pure gold before it is presented to a recipient. If the area of the award is 55.0 cm2 and will be plated with 3.00 m of Au, what mass of Au will be plated on the award?...
Assign oxidation numbers to the atoms in each substance. a. Kr (krypton) b. krypton tetrafluoride (KrF4) c. dioxygen difluoride (O2F2)
Assign oxidation numbers to the atoms in each substance. a. Lithium hydride (LiH) b. Potassium peroxide (K2O2) c. Potassium fluoride (KF)
Assign oxidation numbers to the atoms in H3PO4. Discuss.
Assign oxidation numbers to the atoms in each substance. a. NO b. NO2 c. CrCl2 d. CrCl3
Assign oxidation numbers to the atoms in each substance. a. NaH b. N2O3 c. NO2 d. CuNO3
Assign oxidation numbers to the atoms in each substance. a. CH2O b. NH3 c. Rb2SO4 d. Zn(C2H3O2)2
Assign oxidation numbers to the atoms in each substance. a. P4 b. SO3 c. SO32 d. Ca3(PO3)2
A voltaic cell is based on this reaction: Ni + 2Au+ ( Ni2+ + 2Au If the voltage of the cell is 0.33 V, what is the standard reduction potential of the Au+ + e ( Au half reaction?
The drug known as naproxen sodium is the sodium salt of this molecule: (The extra H atoms are omitted for clarity.) Identify the functional group(s) in this molecule. C110
Identify the ester made by reacting these molecules. ?
Identify the ester made by reacting these molecules. +
Name each molecule. a. b. CI
Name each molecule. a. b. 011 C
Name each molecule. a. b. CIC Cl
Draw the structure of the amide formed by reacting hexylamine with ethanoic acid.
What is the difference between a condensation polymer and a copolymer?
Molecules with multiple double bonds can also participate in addition reactions. Draw the structure of the product when allene, CH2=C=CH2, reacts with bromine.
Phenol is hydroxybenzene, the simplest aromatic alcohol. Picric acid is an explosive derivative of phenol whose formal name is 2,4,6-trinitrophenol. With reference to Exercise 19, draw the structure...
Draw the structures of all the possible isomers of butanol. Include branched isomers.
Draw the structure and name of the alcohol whose double elimination would yield the same product as in Exercise 24. Name the molecule as a hydroxyl-substituted compound.
A lactone is an ester that has its ester functional group in a ring. Draw the structure of the smallest possible lactone (which is called acetolactone, which might give you a hint about its...
A piece of metal wire has a volume of 20.2 cm3 and a mass of 159 g. What is the density of the metal? We know that the metal is manganese, iron, or nickel, and these have densities of 7.21 g/cm3,...
a. When you report your weight to someone, how many significant figures do you typically use? b. What is your weight with two significant figures? c. Indicate your weight and the number of...
Analyses of several samples of a material containing only iron and oxygen gave the following results. Could this material be a compound? Mass of Mass of Mass of Oxygen Sample A 1518 g 1.094 g 0.424 g...
A red-orange solid contains only mercury and oxygen. Analyses of three different samples gave the following results. Are the data consistent with the hypothesis that the material is a compound? Mass...
An aquarium has a rectangular cross section that is 47.8 in. by 12.5 in.; it is 19.5 in. high. How many U.S. gallons does the aquarium contain? One U.S. gallon equals exactly 231 in3.
A spherical tank has a radius of 175.0 in. Calculate the volume of the tank in cubic inches; then convert this to Imperial gallons. The volume of a sphere is (4/3) r3, where r is the radius. One...
Hematite (iron ore) weighing 70.7 g was placed in a flask whose volume was 53.2 mL. The flask with hematite was then carefully filled with water and weighed. The hematite and water weighed 109.3 g....
A solid will float on any liquid that is more dense than it is. The volume of a piece of calcite weighing 35.6 g is 12.9 cm3. On which of the following liquids will the calcite float: carbon...
A room measures 10.0 ft 11.0 ft and is 9.0 ft high. What is its volume in liters?
An ice cube measures 3.50 cm on each edge and weighs 39.45 g. a. Calculate the density of ice. b. Calculate the mass of 400.4 mL of water in an ice cube.
When 10.0 g of marble chips (calcium carbonate) is treated with 50.0 mL of hydrochloric acid (density 1.096 g/mL), the marble dissolves, giving a solution and releasing carbon dioxide gas. The...
A steel sphere has a radius of 1.58 in. If this steel has a density of 7.88 g/cm3, what is the mass of the sphere in grams?
A weather balloon filled with helium has a diameter of 3.00 ft. What is the mass in grams of the helium in the balloon at 21oC and normal pressure? The density of helium under these conditions is...
Antarctica, almost completely covered in ice, has an area of 5,500,000 mi2 with an average height of 7500 ft. Without the ice, the height would be only 1500 ft. Estimate the mass of this ice (two...
A sample of an ethanol-water solution has a volume of 54.2 cm3 and a mass of 49.6 g. What is the percentage of ethanol (by mass) in the solution? (Assume that there is no change in volume when the...
A sample of vermilion-colored mineral was weighed in air, then weighed again while suspended in water. An object is buoyed up by the mass of the fluid displaced by the object. In air, the mineral...
An experimenter places a piece of a solid metal weighing 255 g into a graduated cylinder, which she then fills with liquid mercury. After weighing the cylinder and its contents, she removes the solid...
a. Which of the following items have a mass of about 1 g? A grain of sand A paper clip A nickel A 5.0-gallon bucket of water A brick A car b. What is the approximate mass (using SI mass units) of...
Aluminum metal reacts with bromine, a red-brown liquid with a noxious odor. The reaction is vigorous and produces aluminum bromide, a white crystalline substance. A sample of 27.0 g of aluminum...
A sample of mercury(II) oxide was heated to produce mercury metal and oxygen gas. Then the liquid mercury was cooled to 40oC, where it solidified. A glowing wood splint was thrust into the oxygen,...
All of the following processes involve a separation of either a mixture into substances or a compound into elements. For each, decide whether a physical process or a chemical reaction is required. a....
One sphere has a radius of 5.10 cm; another has a radius of 5.00 cm. What is the difference in volume (in cubic centimeters) between the two spheres? Give the answer to the correct number of...
A solid cylinder of iron of circular cross section with a radius of 1.500 cm has a ruler etched along its length. What is the volume of iron contained between the marks labeled 3.10 cm and 3.50 cm?...
A mineral sample has a mass of 5.95 g and a volume of 7.9 cm3. The mineral is either sphalerite (density 4.0 g/cm3), cassiterite (density 6.99 g/cm3), or cinnabar (density 8.10 g/cm3). Which is it?
A submicroscopic particle suspended in a solution has a volume of 1.3 m3. What is this volume in liters?
An antacid tablet weighing 0.853 g contained calcium carbonate as the active ingredient, in addition to an inert binder. When an acid solution weighing 56.519 g was added to the tablet, carbon...
When a mixture of aluminum powder and iron(III) oxide is ignited, it produces molten iron and aluminum oxide. In an experiment, 5.40 g of aluminum was mixed with 18.50 g of iron(III) oxide. At the...
An aqueous solution of ammonium chloride and barium hydroxide is heated, and the compounds react to give off ammonia gas. Barium chloride solution and water are also products. Write a balanced...
A nucleus of mass number 81 contains 46 neutrons. An atomic ion of this element has 36 electrons in it. Write the symbol for this atomic ion (give the symbol for the nucleus and give the ionic charge...
A monatomic ion has a charge of +2. The nucleus of the ion has a mass number of 62. The number of neutrons in the nucleus is 1.21 times that of the number of protons. How many electrons are in the...
A monatomic ion has a charge of +1. The nucleus of the ion has a mass number of 85. The number of neutrons in the nucleus is 1.30 times that of the number of protons. How many electrons are in the...
Aluminum is reacted with sulfur to form a binary compound. Write the balanced chemical reaction and write the name of the compound formed by the reaction.
A monotomic ion has a charge of +3. The nucleus of the ion has a mass number of 27. The number of neutrons in the nucleus is equal to the number of electrons in a S2 ion. Identify the element and...
A small crystal of CaCl2 that weighs 0.12 g contains 6.5 1020 formula units of CaCl2. What is the total number of ions (cations and anions) that make up this crystal?
There are 2.619 1022 atoms in 1.000 g of sodium. Assume that sodium atoms are spheres of radius 1.86 and that they are lined up side by side. How many miles in length is the line of sodium atoms?
A sample of green crystals of nickel(II) sulfate heptahydrate was heated carefully to produce the bluish green nickel(II) sulfate hexahydrate. What are the formulas of the hydrates? If 8.753 g of the...
A sample of metallic element X, weighing 3.177 g, combines with 0.6015 L of O2 gas (at normal pressure and 20.0oC) to form the metal oxide with the formula XO. If the density of O2 gas under these...
Explain the operation of a cathode-ray tube. Describe the deflection of cathode rays by electrically charged plates placed within the cathode-ray tube. What does this imply about cathode rays?
A student has determined the mass-to-charge ratio for an electron to be 5.64 1012 kg/C. In another experiment, using Millikans oil-drop apparatus, he found the charge on the electron to be 1.605 ...
Ammonia is a gas with a characteristic pungent odor. It is sold as a water solution for use in household cleaning. The gas is a compound of nitrogen and hydrogen in the atomic ratio 1: 3. A sample of...