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The fluoride ion is very toxic.

The fluoride ion is very toxic. Not only does it interfere with glycolysis, but if forms an insoluble precipitate with calcium ions (Ksp = 4.13 x 10-11). Give an explanation as to why CaF2 is insoluble; whereas, other calcium halides are soluble in the order CaI2>CaBr2>CaCl2. How much fluoride (as sodium fluoride) would you h

Stochiometery 4

When 19.8g butane, C4H10 is burned with excess oxygen: 2C4H10g + 13O2g -----> 8CO2g +10H2Og How many grams of oxyen are consumed, how many grams of CO2 & H2O are produced?

Combustion reaction of C4H10O

Consider the following reaction: C4H10O + 6O2-> 4CO2+5H2O deltaH=-2713kj How many grams of water will be produced if the reaction is conducted with 75.6g of C4H10O and 95.5 g of oxygen?

A sample of unknown Y is subjected to elemental analysis

1. A sample of unknown Y is subjected to elemental analysis. The follwoing precentages by weight are found to be: C 40.0% H 6.7% O remainder of % by weight The molar mass is found to be 60.0 g A. Calculate the empirical formula (show work) B. What is the molecular formula of unknown Y. (Inclu

Calculate amount of moles from dissolution

How many total moles of ions are released when each of the following samples dissolves completely in water? (a) 0.24 mol of Na3PO4 mol (b) 51.4 g of NiBr2 3 H2O mol (c) 4.07 1022 formula units of FeCl3 mol

General Chemistry

I need to create 1.0 M solution with 5.21 grams of Na2CO3. I need to create 1.0 M solution with 4.12 grams of NaHCO3 . How much distilled water to is use to create these 1.0 M solutions.

Formation of a gas

A solution containing an unknown amount of methyl alcohol that is dissolved in n-octane is added to an excess of methylmagnesium iodide which is dissolved in the high boiling solvent, n-butyl ether. A gas is evolved from the reaction. The gas is collected and its volume determined to be 1.04 ml (corrected to STP). What is the


1. Calculate each of the following quantities. a. grams of solute in 173.4 mL of 0.207 M calcium acetate b. molarity of 576 mL solution containing 21.1 g of potassium iodide c. moles of solute in 145.6 L of 0.726 M sodium cyanide 2. Assuming that the volumes are additive, what is the concentration of KBr in a solution prep

Average Density of the Sun

I need some help figuring this question out: The sun has estimated mass of 2x10^36 and the sphere is of average radius of 6.96x10^5 km, calculate the average density of the sun in units of kg/km^3; kg/m^3; g/cm^3 and lbs./ml (hint: use answer from c to convert).

Natural Phenomena Experiment

My son needs to demonstrate an experiment that can explain natural phenomena or the world of everyday experiences using scientific methods and employ theories to interpret his observations. Any ideas, material lists and steps would be helpful.

Modifying the determination of density of a solid in water

How would you modify the determination of density of a solid if the solid dissolved in water, as sugar does? Would your density measurements be more precise if you used a balance that weighed to more decimal places, but still used the same graduated cylinder for determining the volume?

Mole problem - package of M&M candies contains 50 pieces

A package of M&M candies contains 50 pieces. What fraction of a mole is this? Express in both normal and scientific notation. A package of 50 m&m candies cost 50 cents. How much would a mole of m&m's cost in dollars? Given the annual budget of the US is 2 trillion dollars, how many years would it take the US to pay for a mol

Mole problem - The volume of an M&M candy

The volume of an m&m candy is .65 mL. What volume in cubic meters, would one mole of m&m candies occupy? Next, compare the volume of a mole of m&m's to lake erie, which has a volume of 116 mi^3. How many lakes the size of lake erie would a mole of M&M candies fill.

Solutions, Density, Molecular weight

The alcohol content of hard liquor is normally given in terms of the "proof", which is defined as twice the percentage by volume of ethanol (C2H5OH) present. Calculate the number of grams of alcohol present in 1.00 L of 51 proof gin. The density of ethanol is 0.798 g/mol. (solution in grams, please) Arginine vasopressin is

Determining a molecular formula

Thriophene is a carbon-hydrogen-sulfur compound used in the manufacture of pharmaceuticals. When burned completely in excess oxygen, its combustion products are CO2, H2O, and SO2. Combustion of a 0.535 g sample yields 1.119 g CO2, 0.229 g H2O, and 0.407 g SO2. What is the empirical formula of thiophene? The molar mass of thiophe

General Chemistry

I have premass samples of NaCl (1.16 grams) and CaCl2 (2.24 grams), I need to create a 1.0M solution of both slats using distilled water. How much distilled water do I use per salt?


An empty vial weighs 55.32g. 1) If the vial weighs 185.56g when filled with liquid mercury (d=13.53 g/cm^3), what is its volume? 2) How much would the vial weigh if it were filled with water (d = 0.997g/cm^3 at 25 degrees Celsius)? [show all your steps in answering this question] Volume of the vial

Structures of Hydrocarbons

Unlike cyclopentadiene, 1,3 cyclohexadiene can be stored for long periods at room temperature. When 1,3 cyclohexadiene is heated at 180 degrees C for two hours, a 30% yield of two products A and B, each of empirical formula C12H6, can be isolated. Hydrogenation of either A or B gives the same hydrocarbon C, of empirical formula

Finding atoms in a sample

Avogradro's number (6.022 x 10^23 atoms/mol) is a useful number that can be used to calculate a number of different values for compounds/elements. One important value is finding the number of atoms in a specific mass of an element. The solution includes a general step-by-step method of finding the number of atoms in a specific

Molar problem

Question: If you want to make 2.5 liters of a 1.2 Molar solution of Iron(III)nitrate, how many grams of Iron(III) nitrate would you need to weigh out? This is a beginners easy class, so the teacher keeps it simple and not complex. We figure out the problems using conversion factors and I want to know how to set it up and h

Aluminum Nitrate

How many grams of aluminum nitrate would be needed to make 0.95 ml of a solution with a normality of 3.2? I need to know how to set up this problem and then make sure I end up getting the right answer on the calculator.

Molal Solution/Mass of Water and Mole Fraction

What mass of water must be used to dissolve 20.0 g of C2H5OH to prepare a 0.0500 molal solution of ethanol? 8.70Kg how? Calculate the mole fraction of ethyl alcohol C2H5OH in a solution that contains 230 grams of C2H5OH and 312 grams of benzene C6H6? 0.56 How?

Molality/molarity calculations

Please help me calculate the molality of a solution that contains 51.2 g of C10H8 in 500 ml of carbon tetrachloride. The density of CCl4 is 1.60 g/ml. I also need help calculating the molarity of a solution that contains 9.0 g of (COOH)2 in 1500 ml of solution.