Calculate the percentage, by mass, of carbon in sodium hydrogencarbonate (NaHCO3)

When faced with this style of problem there are steps to correctly answer the quesion:

Step 1 - identify the atomic mass of carbon

Step 2 - calculate the atomic mass of the compound

Step 3 - work out the percentage, by mass, of carbon in the compound

Method:

Step 1:

To  calculate the atomic mass, a periodic table is required. The atomic mass of each element is located at the top of the element, displayed as a number. In this case carbon has an atomic mass of 12 g/mol.

Step 2:

The same principles in step 1 are required and applied to the remaining atoms in the compound - sodium hydrogen carbonate. The atoms in the compound are sodium (Na), hydrogen (H), carbon (C) and oxygen (O). Looking at the value of atomic mass on the periodic table, the values of atomic mass are as follows:

Na = 23 g/mol

H = 1 g/mol

C = 12 g/mol

O = 16 g/mol

There is 1 Na atom, 1 H atom, 1 C atom and 3 O atoms in the compound. Now add these values together to get the atomic mass of the compound as such:

23+1+12+(3*16) = 84 g/mol

Step 3:

Now the percentage, by mass, needs to be calculated. The general rule for calculating a percentage is:

percentage = (value/total)*100%

Therefore by applying this rule for our problem we find that

Percentage = (12/84)*100% = 14.3 % (to 1 d.p)

HT
Answered by Hayden T. Chemistry tutor

41673 Views

See similar Chemistry GCSE tutors

Related Chemistry GCSE answers

All answers ▸

Describe how to separate hydrocarbons of different lengths


Propane burns completely to produce carbon dioxide and water. Describe how you would use limewater to show that carbon dioxide is produced.


Name and describe the type of bond in sodium chloride


25cm3 NaOH was titrated with 0.05mol dm-3 HCl. 21.5m3 of HCl neutralised 25cm3 of NaOH. What is the concentration of NaOH in mol dm-3?


We're here to help

contact us iconContact ustelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

© MyTutorWeb Ltd 2013–2025

Terms & Conditions|Privacy Policy
Cookie Preferences