During an effusion experiment, a certain number of moles of an unknown gas passed through a tiny hole in 50 seconds. Under the same conditions, the same number of moles of oxygen gas passes through the hole in 30 seconds. What is the molar mass of the unknown gas? pl help me

In a laboratory, 1.55mg of an organic compound containing carbon, hydrogen, and oxygen is burned for analysis. this combustion resulted in the formation of 1.45mg of carbon dioxide and .89 mg of water. what is the empirical formula for this compound?

Select the word from the list that best fits the definition the nuclear family into which a person is born or adopted.

Acalorimeter is to be calibrated: 51.203 g of water at 55.2 degree c is added to a calorimeter containing 49.783 g of water at 23.5c. after stirring and waiting for the system to equilibrate, the final temperature reached is 37.6 degree c. specific heat capacity of water (s = 4.18 j/g∙degree c). calculate the calorimeter constant. (smδt)warm water = -[(smδt)cold water + (calorimeterδtcold water)]