Acompound containing the elements c, h, n, & o is analyzed. when a 1.2359 g sample is burned in excess oxygen, 2.241 g of co2(g) is formed. the combustion analysis also showed that the sample contained 0.0648 g of h.
(i) determine the mass, in grams, of c in the 1.2359 g sample
(ii) when the compound is analyzed for n content only, the mass percent of n is found to be 28.84%.
(iii) determine the mass, in grams, of o in the original 1.2359 g sample of the compound.
(iv) determine the empirical formula of the compound.

In the reading, yao chen-yuan describes traveling to deliver a message. why was he willing to risk danger to travelto tientsin? he wanted to the boxers with their cause

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

Abeaker with 2.00×102 ml of an acetic acid buffer with a ph of 5.000 is sitting on a benchtop. the total molarity of acid and conjugate base in this buffer is 0.100 m. a student adds 4.70 ml of a 0.360 m hcl solution to the beaker. how much will the ph change? the pka of acetic acid is 4.740.