Josh decided to mix some vinegar with baking soda. he knew that a reaction occurred because he made careful observations. he noted that the mixture started to foam up and bubble and was white in color. how did josh know that a chemical reaction occured? he was sure a reaction occurred because of a) the formation of a gas. b) the color of the mixture. c) the smell of the vinegar. d) the volume of the mixture.

its A

Explanation: i did the test myself so i know its A

the ideal gas law equation is as follows

pv = nrt

where p - pressure

v - volume

n - number of moles

r - universal gas constant

t - temperature

so if the pressure, volume and temperature are already known

we are left with n and r

since r is the universal gas constant that has a known fixed value then r too is known

so we are left with 'n'

once we know temperature volume and pressure

we can find the number of moles of gas present using the ideal gas law equation

this is not my own answer, this is an answer for the same question by the user blahblahmali. i do not claim ownership of this account.

the answer would be a