Homework Help

'ENO' Ingredients: Sodium Bicarbonate 46.4 percent,citric acid:43.6 percent,sodium...

user profile pic

phanpal999 | Student, Grade 8 | (Level 1) Salutatorian

Posted April 9, 2013 at 12:28 PM via web

dislike 1 like

'ENO' Ingredients: Sodium Bicarbonate 46.4 percent,citric acid:43.6 percent,sodium carbonate:10 percent

Describe a confirmatory test for the gas produced by the reaction between 'ENO' and water

1 Answer | Add Yours

user profile pic

jerichorayel | College Teacher | (Level 1) Senior Educator

Posted April 10, 2013 at 4:59 AM (Answer #1)

dislike 1 like

ENO is an antacid (manufactured by GSK) which contains a mixture of sodium bicarbonate (`NaHCO_3` ), citric acid (`H_3C_6H_5O_7` ) and sodium carbonate (`Na_2CO_3` ). Initially, citric acid is inert when dry (or anhydrous). Upon the addition of water, the citric acid will start to dissociate and eventually becomes reactive. It can convert the carbonates into Carbon dioxide and water.

The general reaction for this can be written as:

ENO (s) + water (l) -> citrate (salt) + carbon dioxide (g) + water (l)

We can see that among the products, carbon dioxide is the gas that will be produced in the reaction. To confirm the presence of carbon dioxide in the solution, effervescence should be noticed. You can also bubble the gas produced over lime water. If the lime water turns cloudy, carbon dioxide is present.


Join to answer this question

Join a community of thousands of dedicated teachers and students.

Join eNotes