Monday

April 27, 2015

April 27, 2015

Total # Posts: 610

**Chemistry**

Ethanol boils at a temp. of 78.29 degrees C. What amount of energy, in joules, is necessary to heat to boiling and then completely vaporize a 23 g sample of ethanol initially at 12 degrees C? I know that the molar enthalpy heat of vaporization is 35.56 kJ/mol and the specific ...
*May 14, 2007*

**Algebra help needed!**

Recall that on some roads, a skid mark of length L ft. indicates that a car was traveling at least s mph, where s is approx. 2 times the square root of 5L. If a car stopped quickly from a speed of 55 mph, about how long would the skid marks be? Please note that we don't do...
*May 3, 2007*

**Chem help!!**

A rock salt (NaCl), ice, and water mixutre is used to make homemade ice cream. How many grams of rock salt must be added to lower the freezing point 10.0 degrees C? I have no idea what to do, please help! delta T = Kf*i*m delta T = 10. Kf is the molal freezing point constant, ...
*May 3, 2007*

**Chemistry URGENT**

I have to match the items to the statements below, and I'm stuck! My answers are in parentheses, but I know that some of them are wrong. Please help if you know how...I would GREATLY appreciate it! A Dilute B Unsaturated C Saturated D Supersaturated 1. Sodium acetate ...
*April 24, 2007*

**Chemistry**

I have to match the items to the statements below, and I'm stuck! A Dilute B Unsaturated C Saturated D Supersaturated 1. Sodium acetate solution after the excess solute fell out of solution. 2. There is visible solute on the bottom of the container. 3. The solution will ...
*April 24, 2007*

**Physics**

Use kx=mg+ma 857x = (5.9*9.8) + (5.9*.81) thus, x= .073
*March 29, 2007*

**chemistry check**

1)A pocket of gas is discovered in a deep drilling operation. The gas has a temperature of 480c and is at a pressure of 12.8 atm. What volume of gas is required to provide 18.0 L of gas at the surface where the conditions are 22 C and 1.00 atm? is this correct for number 1? ...
*March 25, 2007*

**science**

Hi I have 2 questions I hope someone can help me :) 1)A pocket of gas is discovered in a deep drilling operation. The gas has a temperature of 480c and is at a pressure of 12.8 atm. What volume of gas is required to provide 18.0 L of gas at the surface where the conditions are...
*March 25, 2007*

**Math**

Question 1 : We would like to test 3 different treatments on a particu- lar type of plant. A worker at the local greenhouse will allow us to use 3 among 10 plants. Note: Each treatment will be used on one and only one plant. a) In how many different ways can we assign the ...
*September 25, 2006*

**physics**

Given that the distancef rom Earth to the Moon is 3.8 x 10^8 m, that the Moon takes 27 days to orbit Earth, and that the mass of the Moon is 7.4 x 10^22 kg, what is the acceleration of the Moon and the size of the attractive force between Earth and Moon? Use v = (2pir)/T, ...
*September 18, 2006*