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Types of analysis The residents in a neighborhood near a hazardous-waste disposal site are concerned that it is leaking contaminants into their groundwater.

what mass of concentrated sulfuric acid (96% solution of H2SO4) and water is needed to prepare 500g of 10% solution of H2SO4?

The reaction will remove Arsenic concentration from water by promoting the precipitation of arsenic with sulfate to form a mineral. Sulfate concentration in the solution is 2.5 M (remains constant throughout the reaction) but the change of As concentration with time is shown in the table below.

• order of the reaction?  rate constant? 
• How long will it take to decrease the arsenic concentration below New Jersey drinking water standard of 5 µg/L?

(Please include the units as well.)

A groundwater aquifer(closed-system) with no exchange with the atmosphere. Some people have measured 2 main underground rivers as the main inputs for the system, and it can be assumed that the initial species that will form the aquifer are 10^-4 M HAc (pK_a = 4.76), 10^-4 M NH₄Cl (pK_a = 9.25), 10^-3 M NaHCO₃, and 10^-3 M Na₂CO₃ (pK_a1 = 6.35, pK_a2 = 10.33).

 Calculate the pH of the aquifer and the speciation.

At what pH range will this water be well buffered? 

Compound A c6h8 reacts with 2 molar equivalent of hydrogen on catalytic hydrogenation .the ozonolysis of A give 2 moles of  B c3h4o2, follow the DHI concept predict the structure of A ang B

What would the NO_{2 (g)} and SO_{2 (g)} concentrations be at equilibrium if 0.100 mol SO_{3 (g)} and 0.200 mol NO _(g) are placed in a 2.0 L container?  

Calculate the solubility at 

one mol of a substance is equal to

Q1: Calculate AH and AS for the following reaction: NHẠNO3(s) + H20(1) → NH4" (aq) + NO; (aq) Compound AH (kJ/mol) AS (J/mol-K) NHẠNO3(s) -200 100 NH4+ (aq) -180.51 199.4 NO3(aq) -405.0 255.4

what would be boiling point of methylene chloride at 650mm Hg ?

Using electron dot diagrams to predict formulas of ionic compounds Sr+Cl

The unknown is colorless, odorless, and neutral. When mixed with NaOH it produced a brown precipitate and when mixed with BaCl2 it produced a white precipitate. Reactions with other halides gave yellow precipitates. What unknown is it? Write the exchange reaction with the unknown and NaOH. Write the balanced reaction between the unknown and BaCl2. Specify the states in all reactions.

Why is  better separation of two liquid achieve by slow rather than fast distillation

Explain the evidence of diagonal relationships on the periodic table 

How do we control retention in gas chromatography assays? 

1.Represent the transfer of electrons from magnesium
to oxygen atoms to assume noble gas configurations.
Use Lewis electron dot symbols

Quantities in Chemical Formula

What units do chemists normally use for density of liquids, solids and gas? Explain the
differences.

Deduce and explain the number of electrons in the highest energy level of strontium atom

What is the mechanism of the reaction below?

In a gravimetric determination of a soluble sulfate the data gathered is presented (see attachment).

1. Calculate the amount of BaCl2 needed for
titration. 

2. Why do we choose Na2SO4 to be the assumed sample?

Calculate the mass of forsterite Mg2SiO4 that contains a billion ×1.000109 magnesium atoms. Be sure your answer has a unit symbol if necessary, and round it to 4 significant digits.

In a gravimetric determination of a soluble sulfate the data gathered is presented (see the attachment).

1. Calculate the amount of BaCl2 needed for
titration. 

2. Why do we choose Na2SO4 to be the assumed sample?

Classify each of the following acids as monoprotic diprotic and triprotic a)H2SO4  b)HBr  c)H3PO4 d)H2CO3

Why CH3-CH2-CH2-NH2 is more basic than CH3-NH2 ?

How is the structure of a soap micelle similar to the structure of a globular protein?

Which of the following are ionic Lewis structure

2) Write the reaction of elemental solid boron (B) with fluorine gas 'Delta_(I)H' to form '-1135.6" "kJ" "mol^(-1).' for 'BF_(3)(g)' is 'BF_(3)(g).DeltaH' . Calculate the standard enthalpy change for thereaction, delta r h

how to find molarity

Which type of intermolecular attractive Force operates between all molecules

An alloy of chromel containing Ni, Fe, and Cr was analyzed by a complexation titration using EDTA as the titrant. A 0.7176-g sample of the alloy was dissolved in HNO3 and diluted to 250 mL in a volumetric flask. A 50.00-mL aliquot of the sample, treated with pyrophosphate to mask the Fe and Cr, required 26.14 mL of 0.05831 M EDTA to reach the murexide end point. A second 50.00-mL aliquot was treated with hexamethylenetetramine to mask the Cr. Titrating with 0.05831 M EDTA required 35.43 mL to reach the murexide end point. Finally, a third 50.00-mL aliquot was treated with 50.00 mL of 0.05831 M EDTA, and back titrated to the murexide end point with 6.21 mL of 0.06316 M Cu2+. Calculate the weight percentages of Ni, Fe, and Cr in the alloy. 

One component of jojoba oil is a wax formed from eicosenoic acid [ch3(ch2)7ch=ch(ch2)9co2h] and ch3(ch2)7ch=ch(ch2)8oh. Draw the structure of the wax, including the vid geometry of both carbon-carbon double bonds. 

Differences between strength and concentration in acids in points

attached is the question. would appreciate it very much if can provide step by step of how you derive. below is the model answer 

a) MW=270.52g/mol, x=6.01=6. therefore, formula is FeCl3.6H2O

b) 28.79% w/w

Quantities in chemical formula

Calculate how much mercury is emitted from coal each minute, if 2 metric tons of coal is burned per minute in large power plants. Assume that the concentration of mercury is the same as in the Earth crust(50 nanogram/g).

How the intermolecular force occur hydrogen bonding

Quantities in Chemical formula