Which scenario will result in the greatest decrease in energy for the system?

(a) The system releases 234 cal of heat and has 430 J of work done to it.

(b) The system gains 904 J of heat and does 23.9 cal of work.

(c) The system does 321 cal of work and loses 2.34 kJ of heat.

(d) The system has 1.09 kJ of work done to it and loses 892 cal of heat.

(e) The system gains 1000. cal of heat and does 4.814 kJ of work.

Find Delta G^o for the following reaction, using delta Hf^o and S^o values.
MnO2(s) + 2CO(g) -> Mn(s) + 2CO2(g)

1 a) What health benefit is derived by adding fluoride to toothpaste or drinking water? What are the possible hazards?

b) What is the present recommended concentration of fluoride in Toronto’s tap water and over the counter toothpaste?

Will all haloalkanes that have ethane as the parent chain not have numbers in the name? Also, could there be a haloalkane with methane as the parent chain. If so, could you give an example?

Need molecular equations (Ionic and net when needed) for the following:

Calcium chloride and sodium carbonate

Copper (II) Nitrate and Sodium Hydroxide

Copper (II) Nitrate and Sodium Sulfate

Magnesium Chloride and Sodium Sulfate

Magnesium Chloride and Sodium Carbonate

Ca + 2 H₂O ------> Ca(OH)₂ + H₂

If we have 4 moles of Ca and 4 moles of water – how much Calcium Hydroxide can we make? What would be the limiting reagent and what would be the one in excess?

Define the terms accuracy and precision. Give examples which illustrate the difference between terms.

Calculate the mass (in  g) of each sample.

6.31×10²⁰ SO3 molecules​

2.4×10²² H2O molecules​

4.6×10²⁵ O3 molecules​

9.85×10¹⁹ CCl2F2 molecules​

drawing a Lewis structure of compound, what are some ways that I can determine if it's polar or nonpolar?

Without calculating the electronegative difference, how can I look at a structure and determine if it's polar or nonpolar?

If given the spectra for 2-Heptanone and Heptanal, how could you tell which is which?

If given the spectra for 2-Heptanone and Heptanoic Acid, how could you tell which is which?

If given the spectra for Tetrahydrofuran and 2-heptanol, how could you tell which is which?

If given the spectra for tetrahydrofuran and ethyl pentanoate, how couldm you tell which is which?

Aqueous hydrochloric acid HCl will react with solid sodium hydroxide NaOH to produce aqueous sodium chloride NaCl and liquid water H2O . Suppose 0.36 g of hydrochloric acid is mixed with 0.164 g of sodium hydroxide. Calculate the maximum mass of water that could be produced by the chemical reaction. Be sure your answer has the correct number of significant digits.

Assignment due soon! Please hurry! Aaaaah!!

You have created a galvanic cell in order to perform the following UNBALANCED reaction. First, balance the reaction. Br- + Ag+ → Br2 + Ag

Part 1: You look up the appropriate reduction potentials for this reaction, and you find the following: Half Reaction Eo (V) Br2 + 2e- → 2Br- 1.11 Ag+ + e- → Ag 0.77 What is the voltage of the reaction given in the introduction? Br- + Ag+ → Br2 + Ag

Part 2: We will use this voltage to calculate K and ΔGo. From your balanced reaction, what number will you use for n?

Part 3: In order to calculate K from ΔG, we must select the appropriate value of R. The question, then, is what units will ΔGo have after the calculation. Note that Faraday's constant (F) has a value of 96500 C/mol, E has units of V, n has units of moles, and 1 V = 1 J/C. Which of the following is the correct value for R? A 0.00831 kJ/(mol*K) B 0.0821 L*atm/(mol*K) C 8.31 J/(mol*K)

Part 4: What is the value of ΔGo for the reaction determined in part 1 (in J/mol)?

Part 5: If the above reaction is carried out at 298 K, what is the value of K?

Calculate the pH of buffers based on the recipes

A: 17.91g Na₂HPO₄*12H₂O

1.7mL 1M NaOH

998.3mL H₂O

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B: 13.16g citric acid monohydrate

25mL 1M NaOH

998.3mL H₂O

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C: 0.49g NaH₂PO₄*H₂O

12.49g Na₂HPO₄*12H₂O

1L H₂O

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D: 17.91g NaH₂PO₄*12H₂O

1L H₂O

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4) The equilibrium constant for the reaction shown below is 4.63 x 10^-3 at 527^oC.

                        COCl₂(g) ó CO(g) + Cl₂(g)

a)Write the equilibrium constant expression in terms of the chemical concentrations.

b)What is the equilibrium constant for the reverse reaction?

c)If 0.50 mol of COCl₂ is placed in a 2.0 L flask, what will the concentration of all of the reactants and products be when the reaction reaches equilibrium at 527^oC?