Which are precautions to take when working with heat and fire? Check all that apply.

What scientific discoveries led to changes in Dalton's atomic theory?

A gas mixture called heliox, 6.11% o2 and 93.89% he by mass, is used in scuba tanks for descents more than 65 m below the surface. calculate the mole fractions of he and o2 in this mixture. he is 0.9980

A noncompetitive inhibitor. binds to the active site of an enzyme a. b. increases the rate of enzyme action alters the primary structure of the enzyme c. d. none of these

A sample of chlorine gas is held at a pressure of 1023.6 kPa. When the pressure is decreased to 8114 kPa the temperature is 36°C, What was the original temperature? Gas Law used:

A room measures 15.0 ft in width and 12.0 ft in length. All of the walls are 9 ft high. If 1 gallon of paint will cover 374 ft^2 per coat of paint, how many gallons of paint would you need to purchase to paint the room with two coats of paint?

What are some chemacial changes in your school?

Which of the following is an example of a double-replacement reaction? A. 3K + AlCl3à 3KCl + Al B. KOH + HBr à KBr + H2O C. CH4 + 2O2à CO2 + 2H2O D. Cu + 2H2SO4à CuSO4 + SO2 + 2H2O

Distinguish between thermal cracking and catalytic cracking

At the end of the reaction you washed the chemicals into a beaker using water. Why was it OK to use water to do this if Grignard reagents are very reactive towards water?

What happens when the electron moves from the first energy level to the second energy level? Energy is absorbed, and an emission line is produced. Energy is released, and an emission line is produced. Energy is absorbed by the atom.