General Chemistry: Atoms First 2nd. Edition by John E. McMurry, Robert C. Fay | 9780321809261 | 0321809262

General Chemistry

General Chemistry: Atoms First

10 SOLVED PROBLEMS

258 SOLVED PROBLEMS

Question: 19.13

calculating the amount of product produced by Electrolysis A constant current of 30.0 A is passed through an aqueous solution of NaCl for 1.00 h. How many grams of NaOH and how many liters of Cl2 gas at STP are produced? ...

Verified Answer:

Because electrons can be thought of as a reactant ...

Question: 6.4

CHEMICAL REACTIONS AND THE OCTET RULE Lithium metal reacts with nitrogen to yield Li3N. What noble-gas configuration does the nitrogen atom in Li3N have? ...

Verified Answer:

The compound

Li_{3}N

contains three...

Question: 11.12

CALCULATING THE OSMOTIC PRESSURE OF A SOLUTION The total concentration of dissolved particles inside red blood cells and in the surrounding plasma is approximately 0.30 M, and the membrane surrounding the cells is semipermeable. What would the maximum osmotic pressure in atmospheres inside the ...

Verified Answer:

\Pi

\left(0.30 \frac{mol}...

Question: 10.7

CALCULATING THE NUMBER OF ATOMS IN A UNIT CELL How many atoms are in one primitive-cubic unit cell of a metal? ...

Verified Answer:

As shown in Figure 10.22a, a primitive-cubic unit ...

Question: 3.16

CALCULATING A PERCENT COMPOSITION FROM A FORMULA Glucose, or blood sugar, has the molecular formula C6H12O6. What is the empirical formula, and what is the percent composition of glucose? ...

Verified Answer:

The empirical formula is found by reducing the sub...

Question: 3.9

CALCULATING A YIELD IN GRAMS, GIVEN A PERCENT YIELD Diethyl ether (C4H10O), the “ether” used medically as an anesthetic, is prepared commercially by treatment of ethyl alcohol (C2H6O) with an acid. How many grams of diethyl ether would you obtain from 40.0 g of ethyl alcohol if the percent yield of ...

Verified Answer:

First, calculate the molar masses of the reactant ...

Question: 8.5

CALCULATING ΔH IN A CALORIMETRY EXPERIMENT Aqueous silver ion reacts with aqueous chloride ion to yield a white precipitate of solid silver chloride: Ag^+(aq) + Cl^-(aq) → AgCl(s) When 10.0 mL of 1.00 M AgNO3 solution is added to 10.0 mL of 1.00 M NaCl solution at 25.0 °C in a calorimeter, a white ...

Verified Answer:

Specific heat = 4.18 J/(g · °C) Mass = (20.0 mL)[l...

Question: 8.3

CALCULATING THE AMOUNT OF HEAT RELEASED IN A REACTION How much heat in kilojoules is evolved when 5.00 g of aluminum reacts with a stoichiometric amount of Fe2O3? 2 Al(s) + Fe2O3(s) → 2 Fe(s) + Al2O3(s) ΔH° = -852 kJ ...

Verified Answer:

The molar mass of Al is 26.98 g/mol, so 5.00 g of ...

Question: 11.1

calculating a Vapor pressure Using the clausius–clapeyron Equation The vapor pressure of ethanol at 34.7 °C is 100.0 mm Hg, and the heat of vaporization of ethanol is 38.6 kJ/mol. What is the vapor pressure of ethanol in millimeters of mercury at 65.0 °C? ...

Verified Answer:

Substitute all known values into the equation and ...

Question: 4.4

calculating the concentration of Ions in a Solution What is the total molar concentration of ions in a 0.350 M solution of the strong electrolyte Na2SO4, assuming complete dissociation? ...

Verified Answer:

Assuming complete dissociation, the total molar co...

Question: 8.10

Using Bond Dissociation Energies to Calculate ΔH° Use the data in Table 8.3 to find an approximate ΔH° in kilojoules for the industrial synthesis of chloroform by reaction of methane with Cl2. CH4(g) + 3 Cl2(g) → CHCl3(g) + 3 HCl(g) STRATEGY Identify all the bonds in the reactants and products, ...

Verified Answer:

The reactants have four C-H bonds and three Cl-Cl ...

Question: 23.3

Converting a Name into a Structure Draw the structure of cis-3-heptene. STRATEGY The name 3-heptene indicates that the molecule has seven carbons (hept-) and has a double bond between carbons 3 and 4. The prefix cis- indicates that the two alkyl groups attached to the double-bond carbons lie on ...

Verified Answer:

\begin{matrix} \qquad\overset{1}{C}H_3\over...

Question: 20.7

Drawing the Structures of Diastereoisomers Draw the structures of all possible diastereoisomers of triamminetrichlorocobalt(III), Co(NH3)3Cl3. ...

Verified Answer:

Two diastereoisomers are possible for an octahedra...

Question: 10.2

Predicting the Presence of a Dipole Moment Would you expect vinyl chloride (H2C=CHCl), the starting material used for preparation of poly(vinyl chloride) polymer, to have a dipole moment? If so, indicate the direction. STRATEGY First, use the VSEPR model described in Section 5.1 to predict the ...

Verified Answer:

Because both carbon atoms have three charge clouds...

Question: 4.11

Drawing Resonance Structures The nitrate ion, NO3^-, has three equivalent oxygen atoms, and its electronic structure is a resonance hybrid of three electron-dot structures. Draw them. STRATEGY Begin as you would for drawing any electron-dot structure. There are 24 valence electrons in the nitrate ...

Verified Answer:

\left[\begin{matrix} \quad:\underset{||}{O}...

Question: 0.3

Using Density to Calculate a Volume What is the volume in cm³ of 454 g of gold? (See Table 0.4.) ...

Verified Answer:

As described in the text, density is mass divided ...

Question: 5.4

Predicting the Hybridization of an Atom Describe the hybridization of the carbon atoms in allene, H2C=C= CH2, and make a rough sketch of the molecule showing its hybrid orbitals. STRATEGY Draw an electron-dot structure of allene to find the number of charge clouds on each atom. Then predict the ...

Verified Answer:

Because the central carbon atom in allene has two ...

Question: 6.5

Converting Mass to Moles How many moles of sucrose are in a tablespoon of sugar containing 2.85 g? (The molar mass of sucrose, C12H22O11, was calculated in Worked Example 6.4 to be 342.0 g/mol) STRATEGY The problem gives the mass of sucrose and asks for a mass-to-mole conversion. Use the molar ...

Verified Answer:

\begin{aligned}2.85 \ \cancel{ g \ sucrose ...

Question: 6.2

Balancing a Chemical Equation The major ingredient in ordinary safety matches is potassium chlorate, KClO3, a substance that can act as a source of oxygen in combustion reactions. Its reaction with ordinary table sugar (sucrose, C12H22O11), for instance, occurs violently to yield potassium ...

Verified Answer:

Step 1 Write the unbalanced equation, making sure ...

Question: 19.2

Exploring Differences between Second- and Third-Row Elements Account for the following observations: (a) CO2 is a gaseous molecular substance, whereas SiO2 is a covalent network solid in which SiO4 tetrahedra are linked to four neighboring SiO4 tetrahedra by shared oxygen atoms. (b) Glass made of ...

Verified Answer:

(a) Because of its small size and good π overlap w...