i need to refill my helium tank which holds 2.5 liters, what in grams do I need to order the supplier?​

Which element forms an ionic bond with flourine? 1) fluorine 2) carbon 3) potassium 4) oxygen

Which of the following is true for the actual yield of a reaction? it is always calculated as a ratio. it is the yield from the excess reactant. it is the yield from the limiting reactant. it is always less than the theoretical yield.

8.98 dm3 of hydrogen gas is collected at 38.8 °c. find the volume the gas will occupy at -39.9 °c if the pressure remains constant.