Question

1b a student records the masses of two reactants (baking soda and vinegar), and then mixes them together. the reactants bubble and foam, forming a paste. the student measures the mass again, and the final mass is slightly less than the sum of the initial masses. considering that mass is supposed to be conserved, which statement is a possible explanation for this \loss\ of mass? (1 point)

some of the mass was left behind in the containers the student used

there was not enough of one of the reactants to form as much product as possible, so some reactant was left over and changed the final mass

pastes are in between a liquid and a solid and they have less mass than solids

the bubbling indicates a gas was formed, so some mass was transferred to the air

Explanation:

The reaction between baking soda (sodium bicarbonate) and vinegar (acetic acid) produces carbon dioxide gas, which is indicated by bubbling. Mass conservation applies to closed systems; if gas escapes into the air (open system), the measured final mass decreases because the gas mass is not included. Other options are incorrect: leftover reactants or container residue do not explain the "loss" as described, and pastes do not have inherently less mass than solids.

Answer:

The bubbling indicates a gas was formed, so some mass was transferred to the air