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Stoichiometry

Understanding molar concentrations/volume /equations

1. molar concentration of a liter solution of HCl that has 65 grams of HCl in it? 2. How many grams of NaCl are needed to make a molar solution of 2 liters? 3. How many grams of a glucose are in 1 liter of 10% mass/vloume glucose solns?

Density, Volume

1. Describe two different ways by which you could measure the volume of a small cube. 2. Which is more dense, lead or brass? 3. If the value occupied by a liquid 48mL and the density if 1.2g/mL, what is the mass of the liquid? 4. A recycling plant has chips of hight density poly(ethylene) (HDPE, d=0.92g.mL) used for pla

Dissolving silver bromide in a fixer solution

Solid silver bromide AgBr (s) is removed from the film by dissolving it in an aqueous "fixer" solution containing sodium thiosulfate, Na2S2O3 (aq). This reaction produces NaBr (aq) and Na3Ag(S2O3)2 (aq), which can be rinsed away from the film. A fixer solution is prepared by dissolving 120g Na2S2O3 in enough water to make 4.00 L

Reaction between acrylonitrile, propylene, ammonia, and oxygen

Acrylonitrile (C3H3N (g)) is synthesized by reacting propylene (C3H6 (g)), ammonia (NH3 (g)), and oxygen (O2 (g)), to make C3H3N (g) and H2O (g). Suppose that 1.00 kg C3H6, 1.50 kg NH3, and 2.00 kg O2 are mixed and the reaction proceeds to completion. What mass of each reactant and product is present after the reaction is comple

Writing a balanced chemical equation for combustion of compound X

A compound "X" is composed of 58.77% C, 13.81% H, and 27.42% N, by mass, and has a molar mass close to 100 g/mol. Use this information to write a balanced chemical equation for the combustion of the compound X, assuming that this reaction produces only CO2, H2O, and N2.

Compound Reaction and Observations

2 elements, X and Y, react to form 2 different compunds. 7.00g of X and 4.50g of Y react completely to produce a compound formula XY. 14.0g of X and 3.00g of Y react completely to produce a compound with formula XaYb. Determine values of a and b consistent with these observations.

Chloroform in trihalomethanes

The maximum detected concentration of trihalomethanes (THMs) in a water system was 62.9 microgram/L, which is below the max. permitted level. THMs are compunds with the formula CHXYZ, where X,Y,Z are various combinations of Cl and Br, and are produced by the disinfection of water. An example is chloroform, CHCl3. If chlorofor

Molecule Dose Calculation

Would you please show how to solve the following problem: A anti-inflammatory medication is entirely composed of C, H, and O, and is 75.69 mass % C and 15.51 mass % O. Its molar mass lies between 150 and 300 g/mol. How many molecules of this medication are contained in a dose of 200 mg?

Moles in a solution

Calculate the number of moles of aluminum in a solution containing 10 grams sample. a. 0.742 mole of Al atoms b. 0.371 mole of Al atoms c. 26.98 mole of Al atoms d. 0.121 mole of Al atoms

Molarity of a HCl Solution

Calculate the molarity of a solution prepared by dissolving 3.12 grams of gaseous HCL in enough water to make 26.8 mL solutions. a. 1.6 M HCL b. 0.8 M HCL c. 3.2M HCL d. 5.4 M HCL

Molar Mass of a Compound from Weight

One molecule of a compound weighs 2.03 E-22 g. Its molar mass is: a. 48 gram per mole b. 92.1 gram per mole c. 114 gram per mole d. 122 gram per mole

Volume of Methane

What volume is occupied by 19.6 gram of methane (CH4) at 27 degree Celsius and 1.59 atm? a. 1.71 L b. 18.9 L c. 27.7 L d. 303 L

Grams in a Solution

How many grams of NaCl are contained in 350 ml of a 0.25 M solution of sodium chloride? a. 41.7 gram b. 5.11 gram c. 14.6 gram d. 87.5 gram

Molality of a mixture

Suppose we had 1.00 mole of sucrose (it's about 342.3 grams) and proceeded to mix it into some water. It would dissolve and make sugar water. We keep adding water, dissolving and stirring until all the solid was gone. We then made sure that when everything was well-mixed, there was exactly 1.00 liter of solution. What would be t

Biology

If solid water were denser than liquid could it cause water pipes to burst - in essence the water pipes underground would burst due to its density and them not being able to withstand to the cold water flow which could contaminatie the groundwater leading to environmental hazards? Or would the opposite be true?

Thermochemistry with Heat of Reactions and Standard Enthalpies

1. (Stoichiometry/Heats of Reactions) a. How many kilojoules of heat energy are released when a 63.4-g sample of magnesium metal is completely converted to magnesium oxide according to the equation below? b. How many grams of oxygen gas are used up during an enthalpy change of -292 kJ? 2 Mg(s) + O2(g) -> 2 MgO(s)

Scientific notations

Am I correct: 1.0 gram = 1,000,000.0 micrograms or 1 x 10^-6 micrograms 1.0 gram = 1,000.0 milligrams or 1 x 10^-3 mg 3.781 micrograms = 3.781 x 10^-6 is this grams? micrograms? Is it 0.000003781 grams ? Is it .003781 mgs or 3.781 x 10^-3 mg? Does this mean that 3

Which has the greatest mass?

Which has the greatest mass, 2 moles of sodium chloride or 5 moles of carbon dioxide? Show all work and include units

Molar mass and formula of compounds

Determine the formula and molar mass for each of these compounds Sodium Chloride Potassium Bicarbonate Calcium Phosphate Sodium Fluoride Ammonium Hydroxide

Mass to charge ratio

What's the mass to charge ratio? Given: 5.64 x 10(to the)-12 kg/C 1.605 x 10 (to the)-19 C What is the mass of the electron?

Volume and final concentration

What would be the steps to solve the following two problems? What volume of 12.0 M HCl is required to make 75.0 mL of 3.50 M HCl? AND What is the final concentration of a solution prepared by diluting 35.0 Ml of 12.0 M HCl to a final volume of 1.20 L?

Concentration of sodium chloeide

What would would the steps to find the concentration of sodium chloride in the final solution if 24.34 mL of 0.113 M BaCl2 completely reacts and the total volume of the reaction is 110.4 mL, give the reaction: BaCl2(aq)+Na2SO4(aq)ds=BaSO4(s)+2NaCl(aq)

Identifying and Classifying Metals

An amateur alchemist claims to have discovered a new metal, which she has named metallium, with the elemental symbol Me. She has carried out an experiment in which a current of 0.500 amps were passed through an aqueous solution of Me(SO4)2 for 45.0 minutes, which deposited 0.682 grams of the metal. Using electrochemistry, show

Lead nitrate and sodium iodide reactions

Please answer the following parts of a question. 1. What is precipitated in the reaction of lead nitrate and sodium iodide. 2. Explain the reasoning in three sententces. 3. Write a balanced ionic equation for the reaction of lead nitrate and sodium iodide. 4. How, qualitatively, will the value of the solution in water of t

Determining Density from Volume

I have a 40 lb container that measures 14x20x30 and need to find the density. I also have another 40 lb container that has a volume of 1.9 gal. How do you find the density for both to see which one is lighter?