If 19.2 g sodium carbonate is obtained from the thermal decomposition of 75.0 g of sodium hydrogen carbonate according to the unbalanced equation,
NaHCO3 → Na2CO3 + H2O + CO2
What is the percent yield?

What is your attempt?

Did you try to find out the number of grams of Na2CO3 that you should be getting from heating 75.0 g of NaHCO3?

If 19.2 g sodium carbonate is obtained from the thermal decomposition of 75.0 g of sodium hydrogen carbonate according to the unbalanced equation,
NaHCO3 → Na2CO3 + H2O + CO2
What is the percent yield?

The yield would be 19.88 Carbonic acid, it all turns to an acid.

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NaHCO3 does not turn to carbonic acid... it gets decomposed by environmental heat.

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NaHCO3 does not turn to carbonic acid... it gets decomposed by environmental heat.

How so?

The equation you posted in your very first post says so.

The equation you posted in your very first post says so.

Sodium Bicarbonate, baking soda... is what we are talking about... it can be either a weak base or acidic. It's a weak base, and it can be an acid.

In neutral solutions it ionizes to Na+ + HCO3-.
The HCO3- can either donate its proton (acid) or accept another (base).
In strong basic solution:
HCO3- + OH- --> CO32- + H2O
In strong acidic solution:
HCO3- + H+ --> H2CO3

Yes, but in this case, there is no acid nor base to react with. NaHCO3 is thus not reacting with an acid/base, but is decomposing.