Bert
Most popular questions and responses by Bert
Organic Chemistry
HCl is added to tpentyl alcohol in a vial to synthesize tpentyl chloride. tpentyl chloride separates on top and the bottom layer is discarded. Sodium bicarbonate is then used to wash the crude tpentyl chloride. What is the purpose of this wash and why
asked on July 7, 2008 
Physics
Suppose you are told that only two colors of light (X and Y) are sent through a glass prism and that X is bent more than Y. Which color travels more slowly in the prism? The one that is bent more travels slower. If white light is sent through a prism, the
asked on March 14, 2007 
Organic Chemistry
What major product is formed by the dehydration of 1,2cyclohexanediol (consider ketoenol tautomerism)?
asked on July 10, 2008 
chemisty
Consider the titration of 50 mL of 0.15 M NH3 with 0.1 M HCl. What is the pH at the equivalence point of the titration? (Kb= 1.8X 105 Ka= 5.6X1010)
asked on December 7, 2007 
Statistics
10. A teacher gives 200 students a study guide for a test and the average score was 90 with a standard deviation of 6. She did not give the other 200 students a study guide and their average score was 70 with a standard deviation of 8. Find the critical
asked on November 11, 2015 
Statistics
10. A teacher gives 200 students a study guide for a test and the average score was 90 with a standard deviation of 6. She did not give the other 200 students a study guide and their average score was 70 with a standard deviation of 8. Find the critical
asked on November 11, 2015 
physics
a uniform beam with a weight of 51.3 N and a length of 3.23 m is hinged at its lower end, and a horizontal force Upper F Overscript rightarrow EndScripts of magnitude 64.0 N acts at its upper end. The beam is held vertical by a cable that makes angle θ =
asked on May 8, 2016 
Chemistry
If 100mL of a 0.10M NaOH solution is added to 75mL of a 0.15 HCl solution, then what is the pH of the resultant solution?
asked on August 22, 2007 
Physics
If a solid glass cylinder is placed above the words Lead Oxide (Lead in red print and Oxide in blue) and viewed from the side, the word Lead appears inverted, but the word Oxide does not. Explain. What part of the cylinder is on top of the letters? From
asked on March 29, 2007 
Statistics
When circuit boards used in the manufacture of compact disc players are tested, it is discovered that each has a 5% chance of being defective. Suppose that a batch of 25 of these circuit boards is randomly selected. Would this be binomial or poission
asked on September 25, 2009 
Cell Biology
What is the theoretical limit of resolution in micrometers when there is a numerical aperture (N.A) of 0.10, 500nm wavelength, and 4X magnification?
asked on August 26, 2008 
Chemistry
50 ml of 5 M H2SO4 react with excess BaCl2 to Make 40 g of BaSO4. a.) What is the theoretical yield of BaSO4? b.) What is the Percentage yield of BaSO4
asked on November 4, 2010 
Organic Chem
NaCl was used to rinse a condenser after distillation of 4methylcyclohexene to remove unreacted phosphoric acid. Why is saturated NaCl used to rinse the glassware rather than water?
asked on July 10, 2008 
Chemistry
A certain shade of blue had a frequency of 1.01*10^4 Hz. What is the energy of exactly one photon of this light?
asked on March 20, 2011 
Science
A 500 mL bottle of water, which is at 25 degrees C, is poured over 120 g of ice at 8 degrees C. What will be the final temperature of the water when all the ice has melted. Assume that container is insulated and does not change temperature.
asked on January 20, 2010 
MATH!!!!!!!
The river boat paddled upstream at 12km/h, stopped for 2 h of sightseeing, and paddled back at 18km/h. How far upstream did the boat travel if the total time for the trip, including the stop, was 7h? Please help me, the answer is 36 km but i have no idea
asked on January 8, 2008 
History
What was the relationship between church and state during the 16th Protestent Reformation?
asked on August 26, 2007 
Physics
If the critical frequency of a lowpass filter is 5 kHz, what is the filter bandwidth?
asked on April 5, 2012 
Physics
If the two input voltages to a 2input summing amplifier are +2 V and +5 V, what is the output voltage?
asked on April 4, 2012 
Science
A 500 mL bottle of water, which is at 25 degrees C, is poured over 120 g of ice at 8 degrees C. What will be the final temperature of the water when all the ice has melted. Assume that container is insulated and does not change temperature.
asked on January 21, 2010 
differential geometry
given a circle in S^2 with radius p in the spherical metric, show its area is 2pi(1cos p)
asked on May 4, 2009 
History
During the 16th century protestent reformation, what was the relationship between the church and state? http://en.wikipedia.org/wiki/Protestant_reformation Let us know what you conclude, and someone here will be able to critique your thinking. =)
asked on August 20, 2007 
Physics
Two cars are parked on a street. A third car hits the back of the second car and causes all of the cars to move. (Ignore the distance between the cars). Calculate: (a)The acceleration of the whole system; (b)the net force on each car; (c)the contact force
asked on March 14, 2014 
Physics
A mountain climber dangles his water bottle and feels the bottle makes an angle of 25 degrees with respect to the vertical line. If his acceleration takes 18 seconds, calculate the speed of the climber.
asked on March 14, 2014 
math
Together, Misty and Keith caught 29 fish. Keith caught 5 fewer fish than Misty. How many did they each catch?
asked on October 10, 2012 
Science
Is the answer 26 celsius? Is it possible that the temp is greater than 25 celsius? A 500 mL bottle of water, which is at 25 degrees C, is poured over 120 g of ice at 8 degrees C. What will be the final temperature of the water when all the ice has melted.
asked on January 21, 2010 
Math
The numbers are 45 and 7, how do you calculate the ratio?
asked on August 30, 2007

AlgrebraSystems of Equations
54
posted on February 20, 2017 
physics
36.75
posted on February 5, 2017 
Math
$20
posted on January 4, 2017 
math
Write to least to greatest. 45/6, 7 1/3 , 7, 4
posted on November 17, 2015 
Science
Does c in the equation stand for temperature in celsius?
posted on January 21, 2010 
Science
Does c stand for temperature in celsius?
posted on January 21, 2010 
Science
What do Tf and Hf stand for? Are they constants? Also, is Tf different from tf?
posted on January 20, 2010 
bio
Transformation efficiency = (Total number of cells growing on the agar plate) / (Amount of DNA spread on the agar plate (in µg)). So if the transformation efficiency is 4 x 10^3 and the amount of plasmid on the plate is 0.04 micrograms, then: 4 x 10^3 = x
posted on April 21, 2009 
History
Could it be described as the state taking total control over the church by determining how the church will function? I was thinking that after the Roman Empire established Christianity the primary religion that the state was able to overrule and control
posted on August 26, 2007 
Chemistry
I don't understand where the H+ comes from, I mean I know it comes from the acid, but don't I need an equilibrium constant K to solve for the H+?
posted on August 22, 2007