1. A sample of a compound has a mass of 4.86 g and is composed of Silicon and Oxygen. What is the percent composition if 2.27 g of the mass is Silicon?

2. What is the percent composition of all of the elements in saccharin (C7H5SNO3)?

3. What is the mass of phosphorus in a 25.0lb quantity of sodium phosphate?

Briefly discuss the main difference between the valence bond and molecular orbital treatments of electronic states in molecules. Which is a better representation of molecules with all bond lengths at their equilibrium separation? And which is better when one or more bond lengths are stretched near their dissociation limit? Explain.

You could add solid KCl to the solution to precipitate out AgCl(s). What mass of KCl is needed to precipitate the silver ions from 13.0 mL of 0.180 M AgNO3 solution?

1) describe isoelectric focusing and isopycnic (density) separation techniques 2) why are these real focusing techniques? 3) how are these gradients established in both cases? d) describe the difficulties in using each 4) why is chromatofocusing not a real focusing technique? 5) describe advantages of these techniques and give examples

Part 1) what is the source of solute movement through the capillary? Part 2) what drawbacks does this technique have? Part 3) what are the advantages of this technique?

Be sure to answer all parts.

Find the pH of the equivalence point and the volume (mL) of 0.0707 M KOH needed to reach the equivalence point in the titration of 23.4 mL of 0.0390 M HNO₂.

Volume: mL KOH

pH =

3. What values of the angular momentum (l) and magnetic (ml) quantum numbers are allowed for a principal quantum number (n) of 4? How many orbitals are allowed?

Hi! is there someone famiilar with organic chem that could read and edit my paragraph about my lab report results. Im having trouble making it flow better, but not make it too wordy.

The purpose of this laboratory experiment was to perform an E1 hydration reaction of 2-methylcyclohexanol with phosphoric acid in order to confirm Zaitsev’s rule by generating a mixture of alkene products as depicted in the reaction above. The mixture of products obtained was analyzed via FTIR and gas chromatography (GC) data. Actual isolation of 8.53 g of the product mixture provided a 44% yield. The low percent yield indicated that 2-methylcyclohexanol was not fully distilled and that some of the organic layer was left over after the extraction. The FTIR obtained Csp³-H, Csp²-H, and C=C stretches at 2924 cm^-1, 3002 cm^-1, and ~1650 cm^-1 for all three products respectively, but revealed C-H bending (-CH₃ group) at 1439 cm^-1 as well as C-H bending (trisubstituted alkene) at 795 cm⁼¹. Based on the GC data, the literature BP for methylenecyclohexane (102-103 °C), 3-methylcyclohexene (104-105 °C), 1-methycyclohexene (109-111 °C), corresponded to their retention times respectively: 1.003 min, 1.376 min, and 1.466 min. It also obtained the relative amounts detected in the mixture of having areas of 166, 367, and 2265 respectively. The GC data also confirmed this compound had the largest area of 2264 (80.3%), indicating it was the most abundant in the mixture. From these data, it was concluded the desired product mixtures have been isolated and that this experiment confirmed Zaitsev’s rule by having 1-methylcyclohexene as the major product.

Calculate the pH for each of the following cases in the titration of 50.0ml of 0.110M. HCLO with 0.110M KOH. The ionization constant for HCLO= 4.0*10^-8. a) before adding KOH b) after adding 25ml KOH c) after adding 30ml KOH d) after adding 50ml KOH e) after adding 60ml KOH

if you added 3.2652 g of calcium chloride to your diluted sodium phosphate solution what reaction would occur?

What is the vapor pressure of eugenol during the distillation?

explain the role of ammonia solution, diazonium salt and halogen lamp in developing of the colorful image formed in dye coupling and diazo imaging

Theory of enzymes:

True or False:

___ Enzymes catalyze reactions by increasing the reaction free energy

___ Enzyme are remarkable for their substrate specificity.

___ Enzyme can convert light energy into chemical or mechanical energy

___ Catalytic residues in enzymes can include amino acid side chains, RNA bases, and other organic cofactors

___ Michaelis-Menten kinetic theory only applies to enzymes with single substrates

___ Enzymes bind transition-state analogs more tightly than substrates

___ At high substrate concentration, reactions are rare-limited by how rapidly enzymes convert substrates into products

___ K_m=K_D when k_cat>>k_-1

___ k_cat/K_{M is equivalent to a second-order rate constant}

___ Enzymes can use electrostatics to exceed the rate of diffusion (bimolecualr collision of substrate with enzyme's active site)

___ Drugs that bind to an allosteric site on an enzyme cause a decrease in k_cat

Consider the following reaction and associated equilibrium constant:
aA(g)⇌bB(g), Kc = 1.5

Part A

Find the equilibrium concentrations of A and B for a=1 and b=1. Assume that the initial concentration of A is 1.0 M and that no B is present at the beginning of the reaction.

Express your answers using two significant figures separated by a comma.

[A], [B] = ?M

Part B

Find the equilibrium concentrations of A and B for a=2 and b=2. Assume that the initial concentration of A is 1.0 M and that no B is present at the beginning of the reaction.

Express your answers using two significant figures separated by a comma.

[A], [B] = ?M

Part C

Find the equilibrium concentrations of A and B for a = 2 and b = 1. Assume that the initial concentration of Ais 1.0 M and that no B is present at the beginning of the reaction.

Express your answers using two significant figures separated by a comma.

[A], [B] = ?M