A calorimeter consists of a massless beaker that contains 50.0 grams of solid water (i.e., ice) at −30 °C. Then 800 grams of lead at 70.0 °C are added to the calorimeter. [The specific heat of lead is 130 J kg⋅Cº. ]
a) Find the final temperature of the calorimeter after equilibrium is reached.
b) If the final temperature is 0 °C, what fraction of the ice is melted?
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A protein 13.2 Weight-percent N. A .500 ml Aliquot of protein solution was digested and liberated NH3 was distilled into a beaker containing 10.0mL of .01380 M HCl. Unreacted HCl needed 1.54 mL of .0108 M Ba(OH)2 for titration. What was the concentration of protein (mg/mL)
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-Sugar is dissolved in hot water at 45oC until the mole fraction of water decreases to 0.839. The vapor pressure of pure water at this temperature is 72 torr. What is the vapor pressure (in torr) of water for this solution?
-A 0.800 g sample of a nonvolatile yellow crystalline solid is
dissolved in 23.0 g of benzene, producing a solution that freezes
at 5.10oC. Find the molar mass of the yellow solid in
g/mol.
-A 3.40 g sample of a nonvolatile nonelectrolyte blue crystalline solid is dissolved in 39.2 g of acetic acid, producing a solution that bolis at 119.9oC. Find the molar mass of the blue solid in g/mol.
-What is the osmotic pressure in atm of a 0.275 M solution of NaCl at 0oC?
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At 1 atm, how much energy is required to heat 93.0 g of H2O(s) at –16.0 °C to H2O(g) at 153.0 °C?
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a 25.0mL solution containing 0.60 M HC2H3O2(acetic acid) was titrated with 0.50 M NaOH. Ka of acetic acid is 1.8*10^-5
Calculate pH at initial volume(0mL added)
Calculate pH at 1/2 equivalence point.
Calculate pH at equivalence point.
Calculate pH at 20.00 mL
In: Chemistry
1. What is the cell emf (Eo cell) for electrolysis of molten nickel (II) iodide? (Use Eo values from Appendix E of your lecture text).
2. What reactions would take place at the anode and cathode during electrolysis of an aqueous solution of nickel (II) iodide?
3. Use the Nernst Equation (Equation 7) to calculate Ecell at 25o C for electrolysis of aqueous sodium chloride if the concentration of chlorine in the brine solution is 4.5 M and the partial pressure of Cl2 is 0.001 atmospheres.
4. Chlorine will spontaneously react with iodide to produce chloride and iodine. What is Eo for this reaction.
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Find the pH after 15.00 mL of 0.100 M HCl has been added to 25.00 mL of 0.100 M NH3 solution. Assume volumes are additive.
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The initial concentration for the compounds involved in the reaction displayed were determined to be [PCl5(g)] = 0.4676 mol/L, [PCl3(g)] = 0.6802 mol/L, [Cl2(g)] = 0.1048 mol/L . Calculate the value of the equilibrium constant ( Kc ) at 292.0 °C if the equilibrium concentration of PCl3(g) was 0.6563 mol/L . PCl5(g) = PCl3(g)+Cl2(g)
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1) Know and understand the history of the development of the atomic theory (name the scientist and what they did)
2) State the Law of Consercation of Matter
3) State the Law of Constant Composition (aka Law of Definite Proportions)
a) Be able to calculate percent by mass
4) Name the three subatomic particles of atoms, and know the mass and charge of each particle.
5) Draw a diagram of Thomson's plum-pudding model of the atoms and explain why it has this name
6) Know and understand what alpha particles are and how they contributed to the development of Rutherford's model of the atom
a) draw a diagram of the Rutherford model of the atom and label the nucleus and the element
7) Know and understand how to find the atomic number and atomic mass of each element on the periodic
a) Be able to calculate the number of neutrons using the mass number and atomic number
b) Be able to write the atomic symbol
8) Know and understand what isotopes are and how they are different from each other.
a) Be able to write the full atomic symbol for any isotope
b) Be able to calculate the number of protons and neutrons when provided the full atomic symbol for any isotope
9) Know and understand what the atomic mass (aka atomic weight) of each element is
a) Know the units used for atomic mass
b) Be able to calculate the weighted average values for the atomic mass of an element
10) Know and understand the difference between a group and period in the periodic table
a) Be able to find the group number from the periodic table
11) Know the following sections of the periodic table:
a) Main group elements (representative)
b) Transition metals
c) Landthanides (rare earths)
d) Actinides
e) Metals
f) Nonmetals
g) Metalloids
h) Alkaline metals
i) Alkaline-earth metals
j) Chalcogens
k) Halogens
l) Noble gases
12) Know and understand what an ion is
a) Know and understand the difference between a cation and an anion
b) Know and understand how a cation and an anion are developed
c) Know and understand how to determine the number of protons, neutrons, and electrons for an ion when given the complete symbol of the ion
d) Know and understand how to write the complete symbol of the ion when given the number of protons, neutrons, and electrons for an ion.
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1.What volume of 0.250 M AgNO3(aq) is required to react with 35.0 mL of 0.210 M CaBr2(aq) in the reaction below:
2 AgNO3(aq) + CaBr2 (aq) ® Ca(NO3)2(aq) + 2AgBr(s)
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Q.n.5) In "Extraction of DNA from Straberries, and precipitation of DNA", Write a short description of the DNA.
In: Chemistry
In: Chemistry
Consider the compression at 15.6 C of 0.35 mol H2O(l) from 0.10
atm to 1.00 atm. Calculate the values of ΔG when the process is
carried out:
(a) isothermally and reversibly and (b) isothermally and
irreversibly under a constant external pressure of 1.00 atm. Take
the density of water at this temperature to be equal to 999.1
kg/m3.
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Please show how to work this problem?
In some applications, nickel-cadmium batteries (EMF= 1.30 V) have been replaced by nickel-zinc batteries. The overall cell reaction for this new battery is:
2H2O (l) + 2NiO(OH) (s) + Zn (s) --> 2Ni(OH)2 (s) + Zn(OH)2 (s)
a) What is the cathode half reaction?
b) What is the anode half reaction?
c) What voltage would you expect the nickel-zinc battery will produce?
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A reaction released 1256 J of heat and expands from 1.3L to 14.7L at a constant pressure of 1.04 kPa. What is the total energy change for the system in kJ. Include the correct sign with respect to the system. (1 kPa * L = 1 J)
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