What are the four important steps needed to obtain accurate meting points on a mel-temp? select four options:

1. grind the sample into a fine powder.
2. put the smallest amount you can see in a capillary tube.
3. fill the capillary tube with about 3mm of powder.
4. set the voltage to rise quickly to 20 degrees below the expected temperature, then re-adjust so the temp rises at 2 degrees per minute.
5. set the voltage to rise quickly to 20 degrees below the expected temperature, then re-adjust so the temp rises at 10 degrees per minute.
6. record the temp at which liquid first appears and the temp at which the last crystal disappears.
7. record the temp at which the sample completely melts and the temp when it boils.

Since the gas in your graduated cylinder is a mixture of butane and water vapor, you must determine the partial pressure of the butane, pbutane, alone. to do this, consult a reference and record the partial pressure of the water vapor, pwater, at the temperature you recorded. use the following formula to compute the partial pressure of the butane. pbutane = atmosphere - pwater use the following combined gas law formula and compute the volume that the butane sample will occupy at stp. (hint: convert both temperatures to kelvin.) pbutane x voriginal = pstandard x vfinal troom tstandard use the following ratio and proportion formula to determine the mass of butane needed to occupy a volume of 22.4 l at stp. grams of butane you used “x” grams of butane ml of butane corrected to stp = 22,400 ml compute the theoretical molar mass of butane based on its formula and the atomic masses on the periodic table. compare your experimental results from #3 to the theoretical value of #4, computing a percent error of your findings using this formula: % error = measured value - accepted value x 100 accepted value use the following ratio and proportion formula to determine the mass of butane needed to occupy a volume of 22.4 l at stp. need asap

What is conserved in the reaction shown below? h2(g) + cl2 (g) --> 2hcl(g)a. mass onlyb. mass and moles onlyc. mass, moles, and molecules onlyd. mass, moles, molecules, and volume

What type of electromagnetic waves does the human eye see as the colors red blue or green a visible light waves b radio waves c infrared waves d microwaves