What is the mass (in grams) of 23.00 L of propane vapor (C₃H₈) at STP?

At STP 22.4L of any gas contains 1mol of gas1L contains=0.04mol23L contains=0.04(23)=0.92mol

Now

Molar mass of Propane:-

3(12)+8(1)=44g/mol

The mass of 23.00 L of propane vapor or gas at STP is 45.2466 grams...~

Detailed solution is attached!! :)

The balanced equation of NaOH and H2SO4 would be:

2NaOH + H2SO4 = Na2SO4 + 2H2O

To determine the concentration of NaOH, we first find the moles of NaOH used in the reaction. We start with the the concentration and volume of H2SO4. We do as follows:

2.00 M H2SO4 ( 0.25 L ) = 0.5 mol H2SO4

0.5 mol H2SO4 ( 2 mol NaOH / 1 mol H2SO4) = 1 mol NaOH

Molarity = 1 mol NaOH / 2.00 L NaOH solution = 0.5 M NaOH solution