Explore BrainMass



5. Calculate the sodium ion concentration when 60.0 mL of 6.0 M sodium carbonate is added to 30.0 mL of 1.0 M sodium bicarbonate.

Boiling Point Elevation

I'm doing boiling point elevation and the formula is: deltaT_b = k_b * m * i (k_b = 0.52 degrees C/m for water) I don't know how to use this calculation with this problem: Calculate the boiling point of an aqueous solution containing 3.8% by mass of NaCl. Do I take 3.8% of NaCl's mass of 58.44g? How do I set up the equatio

Density of Oil

If a serving of oil is exactly 1 tablespoon, which has a mass of 14g, and there are 96 servings in the container, what is the density of the oil in grams per milliliter (g/ml)?


A cylindrical bar of gold that is 1.5 in. high and 0.25 in. in diameter has a mass of 23.1987g, as determined on an analytical balance. An empty graduated cylinder is weighed on a triple beam balance and has a mass of 73.7g. After pouring a small amount of liquid into the graduated cylinder, the mass is 79.16g. When the gold cyl

Chemistry Problems

1. The following reaction occurs: CaCO3 + 2H- -> Ca2+ + CO2 +H2O If a 25gm sample of calcium carbonate is added to a 75.5 ml HCl (density = 1.125gm/cm3, 26% HCl by mass), calculate the molarity of the HCL remaining in solution (if any) after the reaction is complete. Assume no volume change. 2. A sample of coc

Conc. of an ideal solution as function of T and position in a strong gravit. field

An ideal solution with solute density 1.05 and solvent density 1.00 is subject to a huge gravity force field, a linear function of postition, F=kr, k is a constant and r is the position along the field. Derive the concentration as a function of T and position r along the field. (Hints: express gravitational potential as functi

Finding limiting reactant, theoretical yield, and actual yield

An electric furnace produces phosphorus by the following reaction: Ca3(PO4)2(s) + C(s)+SiO2(s)= CaSiO3(s)+CO(g)+P(I) An initial reaction mixture contains 1500g calcium phosphate, 250 g carbon and 1000g silicon dioxide. a) What is the limiting reactant? b) What is the theoretical yield of phosphorus? c) After the reaction


Imagine that we give N2(+), O2(+) and (NO)+ ions the same velocity of 30.0 km/s and then send them into a mass spectrometer where the magnetic field strength is B=8.5MN/C. How far would the spot on the photographic plate be from the entry point for each ion, assuming that each ion completes one-half of an orbit. The atomic mas

Simplest Formula Analysis

50.0 g of an oxide of Chromium (Cr) was found to contain 13.28g of potassium (K), 17.68 g of Chromium (Cr) and 19.04 g of oxygen (O). Find the simplest formula...

Determine Concentration of Potassium Chromate to Use (Mohr Titration)

A titration of 0.100 M Cl^- with 0.100 M Ag^+ used an end point where silver chromate gives an orange precipitate. Select the concentration of potassium chromate that must be present so the orange-colored silver chromate precipitate will appear just when 99.5% of the chloride has been precipitated. Given: Ksp of AgCl = 1.0 x 10

Oxygen reactions

Oxygen can be preparead in a lab by the reaction: 2KCLO3 = 2H2(g) + O2(g) Question: How many grams of KCLO3 must be reacted to produce 100 g of O2?

Daltons Law of Partial Pressures

Dry air near sea level has the following composition by volume: N_2, 78.08%; O_2 20.94%; Ar, 0.93%; CO_2 0.05%. the atmospheric pressure is 1.00 atm. calculate the partial pressure of each gas in atm and the concentration of each gas in moles per liter at 0 degrees C.

Gas stoichiometry

C2H5OH burns in air: C_2H_5OH(l)+O_2 --->CO_2(g)+H_2O(l) balance the equation and determine the volume of air in liters at 35.0 C and 790 mmHg required to burn 227 g of ethanol. assume that air is 21.0 percent O_2 by volume.

What is the oxidation reaction for Ag + NaCl?

For my AP chemistry lab, I was supposed to find the percent of silver in a dime. I started out with the formula: Ag + NaCl → AgCl +Na. The dime was put in a covered beaker with NaCl. However, during the experiment oxygen was added as one of the reactants, accidentally. The precipitated silver chloride was obviously con

Mass percentage of sodium chloride in a mixture

A sample of a mixture containing only sodium chloride and potassium chloride has a mass of 3.5650g. When this sample is dissolved in water and excess silver nitrate is added, a white precipitate (silver chloride) forms. After filtration and drying, this precipitate has the mass 7.9143g. What is the mass percentage of sodium ch

Calculating ppm

The chloride in a saline solution was determined by the Volhard method. A 25 ml aliquot of the solution was acidified with 2 ml of dilute HNO3 and treated with 25 ml of .1749 M AgNO3 (fw 169.9), causing precipitation of AgCl. After addition of several ml of nitrobenzene, the solution required 26.40 ml of .1575 M KSCN to reach t

Find the mass percent of Tl2SO4.

The thallium (present as Tl2SO4) in a 7.80-g pesticide sample was precipitated as thallium(I)iodide. Calculate the mass percent of Tl2SO4 in the sample if 0.890g of TlI was recovered.

Atomic masses: relative abundance

The element Europium exists in nature as two isotopes: 151Eu has a mass of 150.9196 amu, and 153Eu has a mass of 152.9209 amu. The average atomic mass of europium is 151.96 amu. Calculate the relative abundance of the two europium isotopes.


A cube of material with a length of 0.044 m and mass of 10.00 X 10 to the negative 1 power kg. What is the density (g/mL)?


What is the density of a 100.000 grams cubic object that has a length of 0.025 meters?