A propellant for rockets is obtained by mixing the liquids hydrazine, N2H4, and dinitrogen tetroxide, N2O4. These compounds react to give gaseous nitrogen, N2, and water vapor, evolving 1049 kJ of...

a. Write the thermochemical equation for the reaction described in Exercise 6.3 for the case involving 1 mol N2H4. b. Write the thermochemical equation for the reverse of the reaction described in...

Suppose 33 mL of 1.20 M HCl is added to 42 mL of a solution containing excess sodium hydroxide, NaOH, in a coffee-cup calorimeter. The solution temperature, originally 25.0oC, rises to 31.8oC. Give...

A solar-powered water pump has photovoltaic cells that protrude from top panels. These cells collect energy from sunlight, storing it momentarily in a battery, which later runs an electric motor that...

Define energy, kinetic energy, potential energy, and internal energy.

A 14.1-mL sample of 0.996 M NaOH is mixed with 32.3 mL of 0.905 MHCl in a coffee-cup calorimeter (see Section 6.6 of your text for a description of a coffee-cup calorimeter). The enthalpy of the...

The sugar arabinose, C5H10O5, is burned completely in oxygen in a calorimeter. C5H10O5(s) + 5O2(g) 5CO2(g) + 5H2O(l) Burning a 0.548-g sample caused the temperature to rise from 20.00oC to 20.54oC....

Ammonium nitrate is an oxidizing agent and can give rise to explosive mixtures. A mixture of 2.00 mol of powdered aluminum and 3.00 mol of ammonium nitrate crystals reacts exothermically, yielding...

What will be the final temperature of a mixture made from 25.0 g of water at 15.0oC, from 45.0 g of water at 50.0oC, and from 15.0 g of water at 37.0oC?

Acetone, CH3COCH3, is a liquid solvent. The enthalpy change at 25oC and 1 atm for the complete burning of 1 mol of acetone in oxygen to give CO2(g) and H2O(l) is 1791 kJ. From this and from data...

What will be the final temperature of a mixture made from equal masses of the following: water at 25.0oC, ethanol at 35.5oC, and iron at 95oC?

Graphite is burned in oxygen to give carbon monoxide and carbon dioxide. If the product mixture is 33% CO and 67% CO2 by mass, what is the heat from the combustion of 1.00 g of graphite?

A sample of natural gas is 80.0% CH4 and 20.0% C2H6 by mass. What is the heat from the combustion of 1.00 g of this mixture? Assume the products are CO2(g) and H2O(l).

A sample containing 2.00 mol of graphite reacts completely with a limited quantity of oxygen at 25oC and 1.0 atm pressure, producing 481 kJ of heat and a mixture of CO and CO2. Calculate the masses...

How much heat is released when a mixture containing 10.0 g CS2 and 10.0 g Cl2 reacts by the following equation? CS2(g) + 3Cl2(g) S2Cl2(g) + CCl4(g); H = 230 kJ

An industrial process for manufacturing sulfuric acid, H2SO4, uses hydrogen sulfide, H2S, from the purification of natural gas. In the first step of this process, the hydrogen sulfide is burned to...

A small car is traveling at twice the speed of a larger car, which has twice the mass of the smaller car. Which car has the greater kinetic energy? (Or do they both have the same kinetic energy?)

A soluble salt, MX2, is added to water in a beaker. The equation for the dissolving of the salt is: MX2(s) M2+(aq) + 2X(aq); H > 0

Ammonia burns in the presence of a copper catalyst to form nitrogen gas. 4NH3(g) + 3O2(g) 2N2(g) + 6H2O(g); H = 1267 kJ What is the enthalpy change to burn 35.8 g of ammonia?

An iron skillet weighing 1.28 kg is heated on a stove to 178oC. Suppose the skillet is cooled to room temperature, 21oC. How much heat energy (in joules) must be removed to effect this cooling? The...

A sample of ethanol, C2H5OH, weighing 2.84 g was burned in an excess of oxygen in a bomb calorimeter. The temperature of the calorimeter rose from 25.00oC to 33.73oC. If the heat capacity of the...

Ammonia will burn in the presence of a platinum catalyst to produce nitric oxide, NO. 4NH3(g) + 5O2(g) 4NO(g) + 6H2O(g) What is the heat of reaction at constant pressure? Use the following...

Acetic acid, CH3COOH, is contained in vinegar. Suppose acetic acid was formed from its elements, according to the following equation: 2C(graphite) + 2H2(g) + O2(g) CH3COOH(l) Find the enthalpy...

Any object, be it a space satellite or a molecule, must attain an initial upward velocity of at least 11.2 km/s in order to escape the gravitational attraction of the earth. What would be the kinetic...

Acetic acid, HC2H3O2, is the sour constituent of vinegar (acetum is Latin for vinegar). In an experiment, 3.58 g of acetic acid was burned. HC2H3O2(l ) + 2O2(g) 2CO2(g) + 2H2O(l ) If 52.0 kJ of heat...

A piece of lead of mass 121.6 g was heated by an electrical coil. From the resistance of the coil, the current, and the time the current flowed, it was calculated that 235 J of heat was added to the...

Acetic acid has the structure CH3CO(OH), in which the OH group is bonded to a C atom. The two carbonoxygen bonds have different lengths. When an acetic acid molecule loses the H from the OH group to...

An ionic compound has the following composition (by mass): Ca, 30.3%; N, 21.2%; O, 48.5%. What are the formula and name of the compound? Write the Lewis formulas for the ions.

A gaseous compound has the following composition by mass: C, 25.0%; H, 2.1%; F, 39.6%; O, 33.3%. Its molecular mass is 48.0 amu. Write the Lewis formula for the molecule.

Assume the values of the CH and CC bond energies given in Table 9.5. Then, using data given in Appendix C, calculate the C=O bond energy in acetaldehyde, Compare your result with the value given in...

According to Pauling, the AB bond energy is equal to the average of the AA and BB bond energies plus an energy contribution from the polar character of the bond: BE(AB) = 1/2 [BE(AA) + BE(BB)] + k(XA...

Arrange the members of each of the following pairs in order of increasing radius and explain the order: a. Sr, Sr2+ b. Br, Br

Arrange the members of each of the following pairs in order of increasing radius and explain the order: a. Te, Te2 b. Al, Al3+

Arrange the following in order of increasing ionic radius: Cl, Na+, and S2. Explain this order. (You may use a periodic table.)

Assuming that the atoms form the normal number of covalent bonds, give the molecular formula of the simplest compound of arsenic and bromine atoms.

Assuming that the atoms form the normal number of covalent bonds, give the molecular formula of the simplest compound of silicon and chlorine atoms.

With the aid of a periodic table (not Figure 9.15), arrange the following in order of increasing electronegativity: a. Sr, Ca, Rb b. Ca, Ge, Ga c. Se, As, Sb

Arrange the following bonds in order of increasing polarity using electronegativities of atoms: PO, CCl, AsBr.

Indicate the partial charges for the bonds given in Problem 9.57, using the symbols + and . Problem 9.57 Arrange the following bonds in order of increasing polarity using electronegativities of...

What hybrid orbitals would be expected for the central atom in each of the following molecules or ions? a. SeCl2 b. NO2 c. CO2 d. COF2

(a) Mercury(II) chloride dissolves in water to give poorly conducting solutions, indicating that the compound is largely nonionized in solution-it dissolves as HgCl2 molecules. Describe the bonding...

What hybrid orbitals would be expected for the central atom in each of the following? a. XeF2 b. BrF5 c. PCl5 d. ClF4+

Assume that the cyanide ion, CN, has molecular orbitals similar to those of a homonuclear diatomic molecule. Write the configuration and bond order of CN. Is a substance of the ion diamagnetic or...

Predict the molecular geometry of the following: a. SnCl2 b. COBr2 c. ICl2 d. PCl6

Acetylsalicylic acid (aspirin) has the structure shown by the following molecular model: Describe the geometry and bonding about the carbon atom shown at the top of the model, in which the carbon...

A molecule XF6 (having no lone pairs) has a dipole moment of zero. (X denotes an unidentified element.) When two atoms of fluorine have been taken away, you get the molecule XF4, which has dipole...

According to the VSEPR model, what molecular geometry would you predict for iodine trichloride, ICl3?

An atom in a molecule is surrounded by four pairs of electrons: one lone pair and three bonding pairs. Describe how the four electron pairs are arranged about the atom. How are any three of these...

An atom in a molecule has one single bond and one triple bond to other atoms. What hybrid orbitals do you expect for this atom? Describe how you arrive at your answer.

A molecular compound is composed of 58.8% Xe, 7.2% O, and 34.0% F, by mass. If the molecular weight is 223 amu, what is the molecular formula? What is the Lewis formula? Predict the molecular...

A student writes the Lewis electron-dot formula for the carbonate anion, CO32, as a. Does this Lewis formula obey the octet rule? Explain. What are the formal charges on the atoms? Try describing the...

An atom in a molecule has two bonds to other atoms and one lone pair. What kind of hybrid orbitals do you expect for this atom? Describe how you arrived at your answer.

A neutral molecule is identified as a tetrafluoride, XF4, where X is an unknown atom. If the molecule has a dipole moment of 0.63 D, can you give some possibilities for the identity of X?

Arrange the following hydrocarbons in order of increasing vapor pressure: ethane, C2H6; propane, C3H8; and butane, C4H10. Explain your answer.

Calculate the percent of volume that is actually occupied by spheres in a face-centered cubic lattice of identical spheres. You can do this by first relating the radius of a sphere, r, to the length...

Acetic acid, the sour constituent of vinegar, has the following structure: Indicate what geometry given below is expected to be found about each of the atoms labeled a, b, and c. - (iv) (iii)

Although a geckos toes stick easily to a wall, their toes lift off a surface just as easily. Explain.

Acetic acid, CH3COOH, forms stable pairs of molecules held together by two hydrogen bonds. Such moleculesthemselves formed by the association of two simpler moleculesare called dimers. The vapor over...

Consider a substance X with a Hvap = 20.3 kJ/mol and Hfus = 9.0 kJ/mol. The melting point, freezing point, and heat capacities of both the solid and liquid X are identical to those of water. a. If...

Identify the phase transition occurring in each of the following. a. The water level in an aquarium tank falls continuously (the tank has no leak). b. A mixture of scrambled eggs placed in a cold...

An electric heater coil provided heat to a 15.5-g sample of iodine, I2, at the rate of 3.48 J/s. It took 4.54 min from the time the iodine began to melt until the iodine was completely melted. What...

As a demonstration, an instructor had a block of ice suspended between two chairs. She then hung a wire over the block of ice, with weights attached to the ends of the wire: Later, at the end of the...

Liquid butane, C4H10, is stored in cylinders to be used as a fuel. Suppose 39.3 g of butane gas is removed from a cylinder. How much heat must be provided to vaporize this much gas? The heat of...

A quantity of ice at 0.0C was added to 33.6 g of water at 21.0C to give water at 0.0C. How much ice was added? The heat of fusion of water is 6.01 kJ/mol and the specific heat is 4.18 J/(gC).

A quantity of ice at 0C is added to 64.3 g of water in a glass at 55C. After the ice melted, the temperature of the water in the glass was 15C. How much ice was added? The heat of fusion of water is...

Carbon disulfide, CS2, is a volatile, flammable liquid. It has a vapor pressure of 400.0 mmHg at 28.0C and 760.0 mmHg at 46.5C. What is the heat of vaporization of this substance?

Use graph paper and sketch the phase diagram of argon, Ar, from the following information: normal melting point, 187C; normal boiling point, 186C; triple point, 189C, 0.68 atm; critical point, 122C,...

A tank of gas at 21°C has a pressure of 1.0 atm. Using the data in the table, answer the following questions. Explain your answers. a. If the tank contains carbon tetrafluoride, CF4, is the...

The heats of vaporization of liquid O2, liquid Ne, and liquid methanol, CH3OH, are 6.8 kJ/mol, 1.8 kJ/mol, and 34.5 kJ/mol, respectively. Are the relative values as you would expect? Explain.

Predict the order of increasing vapor pressure at a given temperature for the following compounds: a. FCH2CH2F b. HOCH2CH2OH c. FCH2CH2OH Explain why you chose this order.

Arrange the following compounds in order of increasing melting point. CaO HC-C-O-C-C-H i441 H-C-C-C-C-O- KCI

Arrange the following substances in order of increasing melting point. Si H-C-O-H H-C-C-H NaCl

Associate each type of solid in the left-hand column with two of the properties in the right hand column. Each property may be used more than once. a. Molecular solid .. low-melting b. Ionic solid ....

Associate each of the solids Co, LiCl, SiC, and CHI3 with one of the following sets of properties. a. A white solid melting at 613C; the liquid is electrically conducting, although the solid is not....

Associate each of the solids BN, P4S3, Pb, and CaCl2 with one of the following sets of properties. a. A bluish white, lustrous solid melting at 327C; the solid is soft and malleable.

Metallic barium has a body-centered cubic structure (all atoms at the lattice points) and a density of 3.51 g/cm3. Assume barium atoms to be spheres. The spheres in a body-centered array occupy 68.0%...

A sample of air at 21C has a relative humidity of 58%. At what temperature will water begin to condense as dew? (See Problem 11.97.) Problem 11.97 The percent relative humidity of a sample of air is...

An experiment calls for 35.0 g of hydrochloric acid that is 20.2% HCl by mass. How many grams of HCl is this? How many grams of water?

Calculate the mole fractions of toluene and benzene in the solution described in Exercise 12.6. Exercise 12.6 Toluene, C6H5CH3, is a liquid compound similar to benzene, C6H6. It is the starting...

A solution is 0.250 mole fraction methanol, CH3OH, and 0.750 mole fraction ethanol, C2H5OH. What is the molality of methanol in the solution?

Maltose, C12H22O11, is a sugar produced by malting (sprouting) grain. A solution of maltose at 25C has an osmotic pressure of 5.50 atm. What is the molar concentration of maltose?

Which aqueous solution has the lower boiling point, 0.10 m KCl or 0.10 m CaCl2?

Phosphoric acid is usually obtained as an 85% phosphoric acid solution. If it is 15 M, what is the density of this solution? What is its molality?

A compound of manganese, carbon, and oxygen contains 28.17% Mn and 30.80% C. When 0.125 g of this compound is dissolved in 5.38 g of cyclohexane, the solution freezes at 5.28C. What is the molecular...

A compound of cobalt, carbon, and oxygen contains 28.10% C and 34.47% Co. When 0.147 g of this compound is dissolved in 6.72 g of cyclohexane, the solution freezes at 5.23C. What is the molecular...

The carbohydrate digitoxose contains 48.64% carbon and 8.16% hydrogen. The addition of 18.0 g of this compound to 100. g of water gives a solution that has a freezing point of -2.2C. a. What is the...

A starch has a molar mass of 3.20 1004 g/mol. If 0.759 g of this starch is dissolved in 112 mL of solution, what is the osmotic pressure, in torr, at 25.00C?

An aqueous solution is 0.797 M magnesium chloride. Given that the density of the solution is 1.108 g/mL, what is the molality of magnesium chloride in this solution?

An experimenter makes up a solution of 0.375 mol Na2CO3, 0.125 mol Ca(NO3)2, and 0.200 mol AgNO3 in 2.000 L of water solution. Note any precipitations that occur, writing a balanced equation for...

An experimenter makes up a solution of 0.310 mol Na3PO4, 0.100 mol Ca(NO3)2, and 0.150 mol AgNO3 in 4.000 L of water solution. Note any precipitations that occur, writing a balanced equation for...

A solution is made up by dissolving 15.0 g Na2CO310H2O in 100.0 g of water. What is the molality of Na2CO3 in this solution?

An aqueous solution is 15.0% by mass of copper(II) sulfate pentahydrate, CuSO45H2O. What is the molarity of CuSO4 in this solution at 20C? The density of this solution at 20C is 1.167 g/mL.

An aqueous solution is 20.0% by mass of sodium thiosulfate pentahydrate, Na2S2O35H2O. What is the molarity of Na2S2O3 in this solution at 20C? The density of this solution at 20C is 1.174 g/mL.

A compound of carbon, hydrogen, and oxygen was burned in oxygen, and 1.000 g of the compound produced 1.434 g CO2 and 0.783 g H2O. In another experiment, 0.1107 g of the compound was dissolved in...

Indicate which of the following is more soluble in ethanol, C2H5OH: acetic acid, CH3COOH, or stearic acid, C17H35COOH.

Arrange the following alkaline-earth-metal iodates in order of increasing solubility in water; explain your reasoning: Ba(IO3)2, Ca(IO3)2, Sr(IO3)2, Mg(IO3)2. IO3 is a large anion.

How would you prepare 72.5 g of an aqueous solution that is 5.00% potassium iodide, KI, by mass?

Fructose, C6H12O6, is a sugar occurring in honey and fruits. The sweetest sugar, it is nearly twice as sweet as sucrose (cane or beet sugar). How much water should be added to 1.75 g of fructose to...

An antiseptic solution contains hydrogen peroxide, H2O2, in water. The solution is 0.600 m H2O2. What is the mole fraction of hydrogen peroxide?

Calculate the vapor pressure at 35C of a solution made by dissolving 20.2 g of sucrose, C12H22O11, in 70.1 g of water. The vapor pressure of pure water at 35C is 42.2 mmHg. What is the vapor-pressure...