(1 mol 6.02 x 10 atomns)

A 0.732 g mixture of methane, CH4, and ethane, C2H6, is burned, yielding 2.046 g of CO2. What is the percentage by mass of CH4 in the mixture? Enter your answer with 2 significant digits.

What is the concentration, in units of grams of dye per liter of solution (g/L), of the dilute dye solution that is produced as follows? Transfer 16.51 mL of the stock solution (6.12 g/L) to a 200.0 mL volumetric flask and dilute to the 200.0 mL line with deionized water. Your answer should be reported to the correct number of significant figures.

A chemist measures the amount of hydrogen gas produced during an experiment. He finds that 575. g of hydrogen gas is produced. Calculate the number of moles of hydrogen gas produced. Round your answer to 3 significant digits. O mol x10 ?

Determine the mass of the product from the following data.    Mass Aluminum Foil (g)      2.5415 Mass Filter Paper (g)      0.2777 Mass Filter Paper + Product (g)      35.6484 Mass Product (g)       Group of answer choices 35.3708 g  35.3705 g  35.3707 g  35.3709 g  35.3706 g

Pheromones are a special type of compound secreted by the females of many insect species to attract the males for mating. One pheromone has the molecular formula C₁9H38O. Normally, the amount of this pheromone secreted by a female insect is about -12 1.4 x 10 g. How many molecules does this quantity contain? Be sure your answer has the correct number of significant digits. molecules

Aqueous hydrobromic acid HBr will react with solid sodium hydroxide NaOH to produce aqueous sodium bromide NaBr and liquid water H2O .Suppose 34. g of hydrobromic acid is mixed with 8.90 g of sodium hydroxide. Calculate the minimum mass of hydrobromic acid that could be left over by the chemical reaction. Round your answer to 2 significant digits.

Determine the mass of the product from the following data.    Mass Aluminum Foil (g)      6.3284 Mass Filter Paper (g)      0.2489 Mass Filter Paper + Product (g)      86.2751 Mass Product (g)       Group of answer choices 86.0263 g    86.0262 g  86.0260 g    86.0264 g    86.0261 g

If a chemist were given 2.99 grams of a mixture of sugar and sand which gave 1.35 grams of sand on analysis of the mixture, what percent by mass of sugar should the chemist report for the composition of the mixture?