A sample of nitrogen gas is at a pressure of 1.20 atm, a volume of 30.0 liters, and a temperature of
87.0 OC. How many moles of gas are in the sample? How many grams of gas are in the
sample?

If a plot weight (in g) vs. volume (in ml) for a metal gave the equation y= 13.41x and r^2=0.9981 what is the density of the metal?

What metric units would you use to measure the thickness of a key

Answer asap need by wednesday morning explain how a buffer works, using an ethanoic acid/sodium ethanoate system including how the system resists changes in ph upon addition of a small amount of base and upon addition of a small amount of acid respectively. include the following calculations in your i. calculate the ph of a solution made by mixing 25cm3 0.1m ch3cooh and 40cm3 0.1m ch3coo-na+. [ka = 1.74 x 10-5 m] ii. calculate the ph following the addition of a 10cm3 portion of 0.08 m naoh to 500cm3 of this buffer solution. iii. calculate the ph following the addition of a 10cm3 portion of 0.08 m hcl to 200cm3 of the original buffer solution.