how many milliliters of dry CO2 measured at STP could be evolved in the reaction between 20.0 mL of 0.100 M NaHCO3 and 30.0 mL of 0.0800 M HCl

Write the equation and balance it.

Convert NaHCO3 to moles. moles = M x L = ?
Convert HCl to moles. moles = M x L = ?

Using the coefficients in the balanced equation, convert moles NaHCO3 to moles CO2.
Do the same for moles HCl.
You will obtain two answers; both can't be right, of course. The correct answer in limiting reagent problems is ALWAYS the smaller one and the reagent producing that value is the limiting reagent.
Then take the smaller value and convert to grams. g = moles x molar mass.

To determine the volume of carbon dioxide (CO2) evolved in the reaction between NaHCO3 and HCl, we need to use the balanced chemical equation and apply the stoichiometry of the reaction.

The balanced chemical equation for the reaction is:
NaHCO3 + HCl -> CO2 + H2O + NaCl

From the equation, we know that 1 mole of NaHCO3 reacts with 1 mole of HCl to produce 1 mole of CO2.

First, let's find the number of moles of NaHCO3 and HCl using the given volumes and concentrations.

Moles of NaHCO3 = volume (in L) × concentration (in mol/L)
= 0.020 L × 0.100 mol/L
= 0.002 mol

Moles of HCl = volume (in L) × concentration (in mol/L)
= 0.030 L × 0.0800 mol/L
= 0.0024 mol

From the stoichiometry of the reaction, we see that the mole ratio of NaHCO3 to CO2 is 1:1. Therefore, the moles of CO2 produced are also 0.002 mol.

Now, we need to convert the moles of CO2 to milliliters at standard temperature and pressure (STP). At STP, the molar volume of any ideal gas is 22.4 L.

Moles to milliliters conversion:
0.002 mol × (22.4 L/1 mol) × (1000 mL/1 L)
= 44.8 mL of CO2

So, approximately 44.8 milliliters of dry CO2 measured at STP could be evolved in the reaction between 20.0 mL of 0.100 M NaHCO3 and 30.0 mL of 0.0800 M HCl.