Question

during a physical science lab investigating chemical reactions, several students placed a 30g antacid tablet in a zip - lock bag that has a mass of 20g. they recorded the masses of the tablet and the bag. then they added 50 grams of water and quickly sealed the bag. the tablet began to fizz and soon disappeared. the bag was filled with gas. what can you conclude about the amount of gas produced if the mass of the liquid after the reaction is completed is still 50 grams? a 30 grams b 50 grams c 60 grams d 90 grams

Explanation:

Step1: Calculate initial total mass

The initial total mass is the sum of the mass of the tablet, the bag and the water. So, $m_{initial}=30 + 20+50=100$ g.

Step2: Determine final mass of non - gas components

The mass of the liquid after the reaction is 50 g and the mass of the bag is 20 g. So the total mass of non - gas components is $m_{non - gas}=50 + 20=70$ g.

Step3: Calculate mass of gas

According to the law of conservation of mass, the mass of gas $m_{gas}=m_{initial}-m_{non - gas}$. So, $m_{gas}=100 - 70 = 30$ g.

Answer:

A. 30 grams