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...

An element has two naturally occurring isotopes with the following masses and abundances: Isotopic Mass (amu) Fractional Abundance 49.9472. 2.500 103 50.9440. 0.9975 What is the atomic mass of this...

A sample of ammonia, NH3, contains 3.3 1021 hydrogen atoms. How many NH3 molecules are in this sample?

A sample of ethanol (ethyl alcohol), C2H5OH, contains 4.2 1023 hydrogen atoms. How many C2H5OH molecules are in this sample?

Ammonium phosphate, (NH4)3PO4, has how many hydrogen atoms for each oxygen atom?

A sample of compound weighing 83.5 g contains 33.4 g of sulfur. The rest is oxygen. What is the empirical formula?

Aluminum chloride, AlCl3, is used as a catalyst in various industrial reactions. It is prepared from hydrogen chloride gas and aluminum metal shavings. 2Al(s) + 6HCl(g) 2AlCl3(s) 3H2(g) Suppose a...

a. What is the mass in grams of a calcium atom, Ca? b. What is the mass in grams of an ethanol molecule, C2H5OH?

Ammonium nitrate, NH4NO3, which is prepared from nitric acid, is used as a nitrogen fertilizer. Calculate the mass percentages of the elements in ammonium nitrate (to three significant figures).

Aniline, a starting compound for urethane plastic foams, consists of C, H, and N. Combustion of such compounds yields CO2, H2O, and N2 as products. If the combustion of 9.71 mg of aniline yields 6.63...

A titanium ore contains rutile (TiO2) plus some iron oxide and silica. When it is heated with carbon in the presence of chlorine, titanium tetrachloride, TiCl4, is formed. TiO2(s) + C(s) + 2Cl2(g) ...

Ethylene oxide, C2H4O, is made by the oxidation of ethylene, C2H4. 2C2H4(g) + O2(g) 2C2H4O(g) Ethylene oxide is used to make ethylene glycol for automobile antifreeze. In a pilot study, 10.6 g of...

A mixture consisting of 11.9 g of calcium fluoride, CaF2, and 10.3 g of sulfuric acid, H2SO4, is heated to drive off hydrogen fluoride, HF. CaF2(s) + H2SO4(l) 2HF(g) + CaSO4(s) What is the maximum...

Alloys, or metallic mixtures, of mercury with another metal are called amalgams. Sodium in sodium amalgam reacts with water. (Mercury does not.) 2Na(s) + 2H2O(l) 2NaOH(aq) + H2(g) If a 15.23-g...

A sample of sandstone consists of silica, SiO2, and calcite, CaCO3. When the sandstone is heated, calcium carbonate, CaCO3, decomposes into calcium oxide, CaO, and carbon dioxide. CaCO3(s) CaO(s) +...

Exactly 4.0 g of hydrogen gas combines with 32 g of oxygen gas according to the following reaction. 2H2 + O2 2H2O a. How many hydrogen molecules are required to completely react with 48 oxygen...

A 3.41-g sample of a metallic element, M, reacts completely with 0.0158 mol of a gas, X2, to form 4.52 g MX. What are the identities of M and X?

An alloy of iron (71.0%), cobalt (12.0%), and molybdenum (17.0%) has a density of 8.20 g/cm3. How many cobalt atoms are there in a cylinder with a radius of 2.50 cm and a length of 10.0 cm?

An exciting, and often loud, chemical demonstration involves the simple reaction of hydrogen gas and oxygen gas to produce water vapor: 2H2(g) + O2(g) 2H2O(g) The reaction is carried out in soap...

Ammonium nitrate, NH4NO3, is used as a nitrogen fertilizer and in explosives. What is the molar mass of NH4NO3?

Calcium sulfate, CaSO4, is a white, crystalline powder. Gypsum is a mineral, or natural substance, that is a hydrate of calcium sulfate. A 1.000-g sample of gypsum contains 0.791 g CaSO4. How many...

A sample of gas mixture from a neon sign contains 0.0856 mol Ne and 0.0254 mol Kr. What are the mass percentages of Ne and Kr in the gas mixture?

A substance has the molecular formula C6H12O2. What is its empirical formula?

An oxide of osmium (symbol Os) is a pale yellow solid. If 2.89 g of the compound contains 2.16 g of osmium, what is its empirical formula?

An oxide of tungsten (symbol W) is a bright yellow solid. If 5.34 g of the compound contains 4.23 g of tungsten, what is its empirical formula?

Acrylic acid, used in the manufacture of acrylic plastics, has the composition 50.0% C, 5.6% H, and 44.4% O. What is its empirical formula?

Two compounds have the same composition: 92.25% C and 7.75% H. a. Obtain the empirical formula corresponding to this composition. b. One of the compounds has a molecular mass of 52.03 amu; the other,...

Adipic acid is used in the manufacture of nylon. The composition of the acid is 49.3% C, 6.9% H, and 43.8% O (by mass), and the molecular mass is 146 amu. What is the molecular formula?...

Nitric acid, HNO3, is manufactured by the Ostwald process, in which nitrogen dioxide, NO2, reacts with water. 3NO2(g) + H2O(l) 2HNO3(aq) + NO(g) How many grams of nitrogen dioxide are required in...

Tungsten metal, W, is used to make incandescent bulb filaments. The metal is produced from the yellow tungsten(VI) oxide,WO3, by reaction with hydrogen. WO3(s) + 3H2(g) W(s) + 3H2O(g) How many grams...

Acrylonitrile, C3H3N, is the starting material for the production of a kind of synthetic fiber (acrylics). It can be made from propylene, C3H6, by reaction with nitric oxide, NO. 4C3H6(g) + 6NO(g) ...

Potassium superoxide, KO2, is used in rebreathing gas masks to generate oxygen. 4KO2(s) + 2H2O(l ) 4KOH(s) + 3O2(g) If a reaction vessel contains 0.25 mol KO2 and 0.15 mol H2O, what is the limiting...

Aspirin (acetylsalicylic acid) is prepared by heating salicylic acid, C7H6O3, with acetic anhydride, C4H6O3. The other product is acetic acid, C2H4O2. C7H6O3 + C4H6O3 C9H8O4 + C2H4O2 What is the...

Caffeine, the stimulant in coffee and tea, has the molecular formula C8H10N4O2. Calculate the mass percentage of each element in the substance. Give the answers to three significant figures.

A sample of sodium chloride, NaCl, weighing 0.0678 g is placed in a 25.0-mL volumetric flask. Enough water is added to dissolve the NaCl, and then the flask is filled to the mark with water and...

How many milliliters of 0.163 M NaCl are required to give 0.0958 g of sodium chloride?

Nickel sulfate, NiSO4, reacts with sodium phosphate, Na3PO4, to give a pale yellow-green precipitate of nickel phosphate, Ni3(PO4)2, and a solution of sodium sulfate, Na2SO4. 3NiSO4(aq) + 2Na3PO4(aq)...

Decide whether a reaction occurs for each of the following. If it does not, write NR after the arrow. If it does, write the balanced molecular equation; then write the net ionic equation. a. Al(OH)3...

An aqueous solution contains 4.50 g of calcium chloride, CaCl2, per liter. What is the molarity of CaCl2? When calcium chloride dissolves in water, the calcium ions, Ca2+, and chloride ions, Cl, in...

An aqueous solution contains 3.45 g of iron(III) sulfate, Fe2(SO4)3, per liter. What is the molarity of Fe2(SO4)3? When the compound dissolves in water, the Fe3 ions and SO42 ions in the crystal go...

An aqueous solution contains 4.00% NH3 (ammonia) by mass. The density of the aqueous ammonia is 0.979 g/mL. What is the molarity of NH3 in the solution?

An antacid tablet has calcium carbonate as the active ingredient; other ingredients include a starch binder. You dissolve the tablet in hydrochloric acid and filter off insoluble material. You add...

A sample of CuSO4 5H2O was heated to 110oC, where it lost water and gave another hydrate of copper(II) ion that contains 32.50% Cu. A 98.77-mg sample of this new hydrate gave 116.66 mg of barium...

A water-soluble compound of gold and chlorine is treated with silver nitrate to convert the chlorine completely to silver chloride, AgCl. In an experiment, 328 mg of the compound gave 464 mg of...

A solution of scandium chloride was treated with silver nitrate. The chlorine in the scandium compound was converted to silver chloride, AgCl. A 58.9-mg sample of scandium chloride gave 167.4 mg of...

An antacid tablet contains sodium hydrogen carbonate, NaHCO3, and inert ingredients. A 0.500-g sample of powdered tablet was mixed with 50.0 mL of 0.190 M HCl (hydrochloric acid). The mixture was...

You order a glass of juice in a restaurant, only to discover that it is warm and too sweet. The sugar concentration of the juice is 3.47 M, but you would like it reduced to a concentration of 1.78 M....

An aluminum nitrate solution is labeled 0.256 M. If 31.6 mL of this solution is diluted to a total of 63.7 mL, calculate the molarity of nitrate ion in the resulting solution.

Zinc acetate is sometimes prescribed by physicians for the treatment of Wilsons disease, which is a genetically caused condition wherein copper accumulates to toxic levels in the body. If you were to...

Arsenic acid, H3AsO4, is a poisonous acid that has been used in the treatment of wood to prevent insect damage. Arsenic acid has three acidic protons. Say you take a 26.14-mL sample of arsenic acid...

Lead(II) nitrate reacts with cesium sulfate in an aqueous precipitation reaction. What are the formulas of lead(II) nitrate and cesium sulfate? Write the molecular equation and net ionic equation for...

Silver nitrate reacts with strontium chloride in an aqueous precipitation reaction. What are the formulas of silver nitrate and strontium chloride? Write the molecular equation and net ionic equation...

Mercury(II) nitrate is treated with hydrogen sulfide, H2S, forming a precipitate and a solution. Write the molecular equation and the net ionic equation for the reaction. An acid is formed; is it...

Iron forms a sulfide with the approximate formula Fe7S8. Assume that the oxidation state of sulfur is 2 and that iron atoms exist in both +2 and +3 oxidation states. What is the ratio of Fe(II) atoms...

A metal, M, was converted to the sulfate,M2(SO4)3. Then a solution of the sulfate was treated with barium chloride to give barium sulfate crystals, which were filtered off. M2(SO4)3(aq) + 3BaCl2(aq) ...

A metal, M, was converted to the chloride, MCl2. Then a solution of the chloride was treated with silver nitrate to give silver chloride crystals, which were filtered from the solution. MCl2(aq) +...

An alloy of aluminum and magnesium was treated with sodium hydroxide solution, in which only aluminum reacts. 2Al(s) + 2NaOH(aq) + 6H2O(l ) 2NaAl(OH)4(aq) + 3H2(g) If a sample of alloy weighing...

An alloy of iron and carbon was treated with sulfuric acid, in which only iron reacts. 2Fe(s) + 3H2SO4(aq) Fe2(SO4)3(aq) + 3H2(g) If a sample of alloy weighing 2.358 g gave 0.1152 g of hydrogen,...

Determine the volume of sulfuric acid solution needed to prepare 37.4 g of aluminum sulfate, Al2(SO4)3, by the reaction 2Al(s) + 3H2SO4(aq) Al2(SO4)3(aq) 3H2(g) The sulfuric acid solution, whose...

Determine the volume of sodium hydroxide solution needed to prepare 26.2 g sodium phosphate, Na3PO4, by the reaction 3NaOH(aq) + H3PO4(aq) Na3PO4(aq) + 3H2O(l) The sodium hydroxide solution, whose...

For each of the following, write molecular and net ionic equations for any precipitation reaction that occurs. If no reaction occurs, indicate this.

A sample of 0.0512 mol of iron(III) chloride, FeCl3, was dissolved in water to give 25.0 mL of solution. What is the molarity of the solution?

An aqueous solution is made from 0.798 g of potassium permanganate, KMnO4. If the volume of solution is 50.0 mL, what is the molarity of KMnO4 in the solution?

A soluble iodide was dissolved in water. Then an excess of silver nitrate, AgNO3, was added to precipitate all of the iodide ion as silver iodide, AgI. If 1.545 g of the soluble iodide gave 2.185 g...

A solution of hydrogen peroxide, H2O2, is titrated with a solution of potassium permanganate, KMnO4. The reaction is 5H2O2(aq) + 2KMnO4(aq) + 3H2SO4(aq) 5O2(g) + 2MnSO4(aq) + K2SO4(aq) + 8H2O(l ) It...

Aluminum metal reacts with perchloric acid to produce hydrogen gas and a solution of aluminum perchlorate. Write the molecular equation for this reaction. Then write the corresponding net ionic...

A volume of carbon dioxide gas, CO2, equal to 20.0 L was collected at 23oC and 1.00 atm pressure. What would be the volume of carbon dioxide collected at 23oC and 0.830 atm?

A sample of a gaseous substance at 25oC and 0.862 atm has a density of 2.26 g/L. What is the molecular mass of the substance?

A given volume of nitrogen, N2, required 68.3 s to effuse from a hole in a chamber. Under the same conditions, another gas required 85.6 s for the same volume to effuse. What is the molecular mass...

A steel bottle contains 12.0 L of a gas at 11.0 atm and 20oC. What is the volume of gas at STP?

A volume of air is taken from the earths surface, at 15oC and 1.00 atm, to the stratosphere, where the temperature is 21oC and the pressure is 1.00 103 atm. By what factor is the volume increased?

A radioactive metal atom decays (goes to another kind of atom) by emitting an alpha particle (He2+ ion). The alpha particles are collected as helium gas. A sample of helium with a volume of 12.05 mL...

The combustion method used to analyze for carbon and hydrogen can be adapted to give percentage N by collecting the nitrogen from combustion of the compound as N2. A sample of a compound weighing...

An 18.6-mL volume of hydrochloric acid reacts completely with a solid sample of MgCO3. The reaction is 2HCl(aq) + MgCO3(s) CO2(g) + H2O(l ) + MgCl2(aq)

A submersible balloon is sent to the bottom of the ocean. On shore, the balloon had a capacity of 162 L when it was filled at 21.0oC and standard pressure. When it reaches the ocean floor, which is...

A rigid 1.0-L container at 75oC is fitted with a gas pressure gauge. A 1.0-mol sample of ideal gas is introduced into the container. a. What would the pressure gauge in the container be reading in...

A sample of a breathing mixture for divers contained 34.3% helium, He; 51.7% nitrogen, N2; and 14.0% oxygen, O2 (by mass). What is the density of this mixture at 22oC and 755 mmHg?

A sample of sodium peroxide, Na2O2, was reacted with an excess of water. 2Na2O2(s) + 2H2O(l ) 4NaOH(aq) + O2(g) All of the sodium peroxide reacted, and the oxygen was collected over water at 21oC....

A sample of zinc metal was reacted with an excess of hydrochloric acid. Zn(s) + 2HCl(aq) ZnCl2(aq) + H2(g) All of the zinc reacted, and the hydrogen gas was collected over water at 17oC; the...

A mixture of N2 and Ne contains equal moles of each gas and has a total mass of 10.0 g. What is the density of this gas mixture at 500 K and 15.00 atm? Assume ideal gas behavior.

A mixture of Ne and Ar gases at 350 K contains twice as many moles of Ne as of Ar and has a total mass of 50.0 g. If the density of the mixture is 4.00 g/L, what is the partial pressure of Ne?

An ideal gas with a density of 3.00 g/L has a pressure of 675 mmHg at 25oC. What is the root-mean-square speed of the molecules of this gas?

A McLeod gauge measures low gas pressures by compressing a known volume of the gas at constant temperature. If 315 cm3 of gas is compressed to a volume of 0.0457 cm3 under a pressure of 2.51 kPa,...

A mole of gas at 0oC and 760 mmHg occupies 22.41 L. What is the volume at 20oC and 760 mmHg?

An experiment called for 4.83 L of sulfur dioxide, SO2, at 0oC and 1.00 atm. What would be the volume of this gas at 25oC and 1.00 atm?

A vessel containing 39.5 cm3 of helium gas at 25oC and 106 kPa was inverted and placed in cold ethanol. As the gas contracted, ethanol was forced into the vessel to maintain the same pressure of...

A sample of 62.3 cm3 of argon gas at 18oC was contained at a pressure of 155 kPa in a J shaped tube with mercury. Later the temperature changed. When the mercury level was adjusted to give the same...

A cylinder of oxygen gas contains 91.3 g O2. If the volume of the cylinder is 8.58 L, what is the pressure of the O2 if the gas temperature is 21oC?

In an experiment, you fill a heavy-walled 5.00-L flask with methane gas, CH4. If the flask contains 7.13 g of methane at 19oC, what is the gas pressure?

An experiment calls for 3.50 mol of chlorine, Cl2. What volume will this be if the gas volume is measured at 34oC and 4.00 atm?

According to your calculations, a reaction should yield 5.67 g of oxygen, O2. What do you expect the volume to be at 23oC and 0.985 atm?

Ammonium chloride, NH4Cl, is a white solid. When heated to 325C, it gives a vapor that is a mixture of ammonia and hydrogen chloride. NH4Cl(s) NH3(g) + HCl(g) Suppose someone contends that the vapor...

Ammonium sulfate is used as a nitrogen and sulfur fertilizer. It is produced by reacting ammonia with sulfuric acid. Write the balanced equation for the reaction of gaseous ammonia with sulfuric acid...

An aqueous solution of ammonium nitrite, NH4NO2, decomposes when heated to give off nitrogen, N2. NH4NO2(s) 2H2O(g) + N2(g) This reaction may be used to prepare pure nitrogen. How many grams of...

An electron, whose mass is 9.11 1031 kg, is accelerated by a positive charge to a speed of 5.0 106 m/s. What is the kinetic energy of the electron in joules? in calories?