A coffee-cup calorimeter initially contains 125 g of water at 24.2⁰C. 10.5 g of Potassium bromide also at 24.2⁰C is added to the water, and after the potassium bromide dissolves, the final temperature is 21.1⁰C. Calculate the enthalpy change for dissolving the salt in J/g and kJ/mol. Assume that the specific heat capacity of the solution is 4.18 J/⁰C g and that no heat is lost.
What is 170 j/g or 20.4 kj/mol
100
When making a 1:3 dilution, 4 mL of water is added to 8 mL of stock solution at 2.50 *10^-5
What is 8.33*10^-7 M
100
List all the intermolecular forces between acetone (CH3COCH3) and Carbon dioxide
What is dispersion
100
What are the units for molality?
What is moles of solute over kg of solvent
200
the balanced net ionic equation for the reaction between aqueous aluminum sulfate and aqueous hydroxide
What is Al^(+3)+3OH^- -->Al(OH)3
200
What is the internal energy of a system when if loses 2302 J of heat and 43.1 kJ of work is done on the system?
Possible equations
q=csm(delta T)
Delta E=q+w
w=-p(Delta V)
What is 20.1 kJ
200
What is the wavelength of a photon going from a n=4 to n=1
What is 97.3 nm
200
Which would likely be soluble in CCL4?
KOH Cl2 NO2 H2S
What is Cl2
200
When looking at freezing point, the effected temperature is always _____ than the freezing temperature of the pure
What is lower
300
The concentration of Pb^2+ is 1.540 mg/mL. What volume of this solution should be diluted to produce 3.7*10^3 L OF A 0.0354 mg/mL of Pb ^2+
What is 85 L
300
Below is the chemical equation for the combustion of Methane. Calculate the quality of heat realease when 33.8g of Oxygen is combusted.
CH4 + O2 --> CO2 + H2O when delta H is -802.2 kJ
What is -1.36*10^3 kJ
300
What type of orbital is described by the following quantum numbers n=5 and l=0. Give an example of an element in this area
What is 5s and rubidium or strontium
300
Which of the following is most likely to be soluble in H2S?
carbon dioxide, Br2, CH4, KOH, NO2
What is KOH and NO2
300
A solution was prepared by dissolving 18.00 g glucose in 150.0 g water. The resulting solution was found to have a boiling point of 10.34⁰C. Calculate how many moles are needed to have a temperature change of .68. Glucose is a molecular solid that is present as individual molecules in solution. If =.51⁰C kg/mol.
What is .2 moles of glucose
400
An object with a mass of 30.22 g is submerged in 70.3 cm cubed of water in a graduated cylinder. The water level increases to 113.9 cm cubed. What is the correct density of the object?
What is 0.693 g/cm cubed
400
A 30.0 g sample of water at 280. K is mixed with 50.0g of water at 330.K calculate the final temperature of the mixture assuming no heat loss to the surroundings.
What is 311 K
400
What is the hybridization, Molecular and electron geometry for phosphate triflouride? Is it polar?
What is SP^3
Tetrahedral
trigonal pyramid
Yes it is polar
400
What type of intermolecular forces will occur between C6H14 and HCN
What is dipole induced
400
Isotonic saline solution, which has the same osomotic pressure as blood, can be prepared by dissolving 0.923 grams of NaCl in enough water to produce 100.0 mL of solution. What is the osmotic pressure, in atmospheres of this solution at 25.0 °Celsius?
What is 7.72 atm
500
Given the unbalanced question, what mass of precipitate wil form when 17 mL of a 0.30 M sodium phosphate solution reacts with a 10.0 mL of a .40 Lead Nitrate Solution
Na3PO4+Pb(NO3)2-->
What is 1.1 g of Pb(PO4)2
500
What is the pressure exerted by a mixture of 5.23 g of H2 and 2.98 g of CH4 at 534 C in a 14.0L
What is 13 atm
500
What is the hybridization, molecular geometry, electron geometry, and bond angles of krypton dichloride? is it polar
What is sp3d2. Liner, octahedral, 180 degrees. No
500
What IMF occurs between CF4 and C6H14
What is dispersion
500
A nonvolatile organic compound Z was used to make up a solution. Solution A contains 5.00 g of Z dissolved in 100. g of water and has a vapor pressure of 754.5 mmHg at the normal boiling point of water. Calculate the molar mass of Z