A helium balloon contains 0.54 g of helium. given the molecular weight of helium is 4.0 g/mol, how many moles of helium does it contain?

What is the formula weight of magnesium nitrate, mg (no3) 2? express your answer to four significant figures and include the appropriate units?

A tank contains 651 L of compressed oxygen gas at a pressure of 122 atm at 25.0 degree C. What is the volume of the oxygen (in L) at a pressure of 745 torr if the temperature remains unchanged? 5.23 L 8 10 times 10^4L 0.184 L 651 L

How many protons, neutrons, and electrons are in a silver atom, with a mass number of 108?

A 100-gram sample of sodium chloride (NaCl) consists of 60.66 g of chlorine and 39.34 g of sodium. What mass of sodium would make up a 150-gram sample of sodium chloride? 89.34 g 39.34 g 59.01 g 64.24 g

A sample contains both CO2 and Ne in unknown quantities. If the sample contains a combined total of 1.25 mol and has a total mass of 47.6 g, what are the percentages of CO2 and Ne in the sample by mass?

Which factors would negatively impact the bodies digestive system

What's a predator? Are predators animals?

Do you think your model accurately represents an alcohol thermometer? How is it like a manufactured thermometer? How is it different?

Democritus contributed to our understanding of the atom in which of the following ways? 1. He determined the mass of the electron. 2. He determined the charge-to-mass ratio for the electron. 3.

A generic gas, x, is placed in a sealed glass jar and decomposes to form gaseous y and solid z. 2x (g) â½ââây (g) + z (s) how are these equilibrium quantities affected by the initial amount of x (g) placed in the container?