Calculate the percentage by mass of nitrogen in an ammonia molecule (NH3) . Take the relative atomic masses of hydrogen and nitrogen to be 1 and 14 respectively.
Calculating the mass of 1 molecule of ammonia:
Mass = ( Number of hydrogen atoms x Mass of hydrogen atom) + ( Number of nitrogen atoms x Mass of nitrogen atoms)
Mass = ( 3 x 1 ) + ( 1 x 14) = 17
Calculating percentage by mass
Percentage by mass of nitrogen = ( Mass of nitrogen atom / Mass of ammonia molecule ) x 100 = ( 14 / 17 ) x 100 = 82%
ND
Related Chemistry GCSE answers
All answers ▸An isotope of Nitrogen has an atomic number of 7 and a mass number of 15. How many electrons, neutrons, and protons does an atom of this isotope have?
The element sulfer is a common componant of coal. When the coal is burned, what pollutant will the sulfer form? How will this new compound impact the environment?
Why does iodine havea higher boiling point compared to chlorine?
Explain why an atom has no overall charge