Aluminum chloride is made from aluminum metal and chlorine gas, as shown:

2Al(s) + 3Cl2(g) ---> 2AlCl3(s)

When 10.0g of aluminum and 25.0g of chlorine are reacted, 18.6g of aluminum chloride is formed. Determine:

a) the limiting reactant

b) the theoretical yield in grams

c) the percent yield for this reaction

d) the excess reactant in grams

A cough medicine contains 0.40% (w/v) dextromethorphan, a cough suppressant, and

1.2% (w/v)

guaifenisin, an expectorant.

How many

milligrams of each drug would you obtain from

3.5 tsp

of cough syrup?

(1 tsp = 4.93 mL)

Consider the following balanced equation: 2N2H4(g)+N2O4(g)→3N2(g)+4H2O(g) Complete the following table showing the appropriate number of moles of reactants and products. If the number of moles of a reactant is provided, fill in the required amount of the other reactant, as well as the moles of each product formed. If the number of moles of a product is provided, fill in the required amount of each reactant to make that amount of product, as well as the amount of the other product that is made.

Balance following simple redox reaction Ca(s) + blank Fe+3(aq) blank + ca+2(aq) + Fe

12. Write the appropriate nuclear symbol for each of the following isotopes: (a) Z = 11, A = 23 (b) Z = 28, A = 64 (c) Z = 50, A = 115 (d) Z = 20, A = 42

20. Ethane and acetylene are two gaseous hydrocarbons. Chemical analysis show that one sample of ethane contains 2.65 g of carbon and 0.668 g of hydrogen, and one sample of acetylene contains 4.56 g of carbon and 0.382 g of hydrogen. Write reasonable empirical formulas for these compounds. Ethane: Acetylene:

22. The atomic masses of 35Cl (75.53%) and 37Cl (24.47%) are 34.968 amu and 36.956 amu, respectively. Calculate the average atomic mass of chlorine. The percentages in parentheses denote the relative abundances ________ amu 26. Consider the combustion of carbon monoxide (CO) in oxygen gas: 2CO(g) + O2(g) → 2CO2(g) Starting with 3.09 moles of CO, calculate the number of moles of CO2 produced if there is enough oxygen gas to react with all the CO

27. The fertilizer ammonium sulfate, (NH4)2SO4, is prepared by the reaction between ammonia (NH3) and sulfuric acid 2NH3(g) + H2SO4(aq) → (NH4)2SO4(aq) How many kilograms of NH3 are needed to produce 3.60 × 105 kg of (NH4)2SO4? Enter your answer in scientific notation.

28. Identify each of the following as a combination, decomposition, or combustion reaction: C2H4O2(l) + 2O2 → 2CO2(g) + 2H2(l) 2Na(s) + Cl2(g) → 2NaCl(s) 2NaH(s) → 2Na(s) + H2(g)

35. (a) What is the Na+ concentration in each of the following solutions: 3.05 M sodium sulfate: M 1.98 M sodium carbonate: M 0.185 M sodium bicarbonate: M (b) What is the concentration of a lithium carbonate solution that is 0.795 M in Li+? 37.A sample of 0.7960 g of an unknown compound containing barium ions (Ba2+) is dissolved in water and treated with an excess of Na2SO4. If the mass of the BaSO4 precipitate formed is 0.8916 g, what is the percent by mass of Ba in the original unknown compound?

20 mL of 15% HCl(v/v)

1000 mL of 10% HCl(w/v)

Give the percentages of the following: 130 mg of HCl + 90 g of H20

How many grams of sodium chloride are there in 0.75 L of a 5% solution?

What weight of NaOH would be required to prepare 500 mL of a 1.5 M solution?

A solution contains 25 g NaCl/L. What is its molarity?

What is the molecular weight of NaCl?

What is the equivalent weight of NaCl?

What is the molecular weight of MgCl2?

What is the equivalent weight of MgCl2?

Describe how to make a 3M solution of Na2SO4

What weight of H2SO4 is required to prepare 500 mL of a 2M solution?

Explain how to prepare a 2N solution of HCl

Explain how to prepare a 3N solution of MgCl2

Please explain how to prepare the following:

400 ml of a 2% glucose solution from a 50% solution available.

A 2% solution of HCL is required for a procedure. A 6% solution is available. How much of the 6% solution will be required to make 1000 mL of a 2% solution?

A procedure calls for acetic acid and water; with the proportions being one part acetic acid to four parts water. 200 mL are needed. How much acetic acid and water are required?

1 L of 70% alcohol is needed. How much 95% alcohol is required to make the 70% solution?

75 mL of a 1N HCL solution is needed. You have a 5N solution available. How will you go about preparing this solution?

Calculate the vapour pressure lowering of a 1M aqueous sucrose (sugar) solution at 25 oC where po(H2O) = 23 mm Hg. The density of 1M sucrose at 25 oC is 1.129 g/mL.

The answer to this question is 0.51 mm Hg

Can you please explain how ti find this?

We know that vapour pressure lowering is DeltaP = X_b * P_A

but how do i find the mole fraction?

Can some one please explain this in detail

Thank you

1) When the Ag⁺ concentration is 1.08 M, the observed cell potential at 298K for an electrochemical cell with the following reaction is 1.654V. What is the Zn²⁺ concentration?

2Ag⁺(aq) + Zn(s) > 2Ag(s) + Zn²⁺(aq)

Answer: ___ M

2) A concentration cell similar to the one shown is composed of two Cr electrodes and solutions of different Cr³⁺concentrations. The left compartment contains 1.32 M Cr³⁺, and the right compartment contains 0.250 M Cr³⁺.


Calculate the cell potential for this reaction at 298 K.

____ volts

In this chromium concentration cell, the compartment on the left is the __anode or cathode__, and the compartment on the right is the _anode or cathode__.

2. How is glycogen breakdown and synthesis regulated in the liver by glucagon and insulin? (Are the processes increased or decreased by these hormones?)

What is the calculated value of the cell potential at 298K for an electrochemical cell with the following reaction, when the Ag+ concentration is 1.49 M and the Al3+ concentration is 3.15×10-4 M ? 3Ag+(aq) + Al(s)3Ag(s) + Al3+(aq)

Answer: in V

The cell reaction as written above is spontaneous for the concentrations given: True or False

What is the calculated value of the cell potential at 298K for an electrochemical cell with the following reaction, when the Ag+ concentration is 5.75×10-4 M and the Mn2+ concentration is 1.24 M ? 2Ag+(aq) + Mn(s)2Ag(s) + Mn2+(aq)

Answer: in V

The cell reaction as written above is spontaneous for the concentrations given: True or False

What is the calculated value of the cell potential at 298K for an electrochemical cell with the following reaction, when the Ag+ concentration is 1.88×10-4 M and the Cr3+ concentration is 1.32 M ? 3Ag+(aq) + Cr(s)3Ag(s) + Cr3+(aq)

Answer: in V The cell reaction as written above is spontaneous for the concentrations given: True or False?

Thank you so much!

cA) [Mn(H₂O)₆]³⁺ (sp³d² octahedral)

B) [Mn(NO₂)₆]^3- (d²sp³ octahedral)

C) [Ni(CN)₄]^2- (square planar)

Please outline only the main steps of an efficient column chromatographic separation of a non-polar compound A from a medium polar compound B and a non-polar chemical (C). C is slightly less polar than A.

explain the difference in properties of diamond and graphite.

-why is graphite black while diamond is not?

-why is graphite very conductive while diamond is not a good conductor of electricity?

-why is graphite soft while diamond is hard

Answer the following questions for the transition metal complex [Mn(CN)₆]^3-.

Using sigma-only considerations:

a) Draw the 5 d orbitals associated with the transition metal center and state whether each one will overlap (strongly, weakly, or not at all) with the ligands (assume sigma bonding only).

b) Using your answer from (a), draw and label the energy levels of the d orbitals (i.e. the d orbital splitting diagram).

c) Fill in the correct number of electrons. Decide whether the complex should be high spin or low spin.

d) Determine the spin state (S) and multiplicity (singlet, triplet, doublet, etc) of the complex.

e) State whether the ligands are pi-donors or pi-acceptors.

f) Draw the 5 d orbitals associated with the transition metal center and state whether each one will overlap (strongly, weakly, or not at all) with the pi-system of the ligands (state whether the ligands are pi-donors or pi-acceptors). Show the pi-overlap in your drawings.

g) Show and discuss the effect that these pi-interactions will have on the d-orbital splitting diagram you drew above.

h) Based on your d orbital splitting diagrams, state whether electronic distortions from ideal geometry are expected and describe how the geometry might distort. Draw the resulting d orbital splitting diagram.