Chemistry
Grade-9
Easy
Question
What is the average atomic mass of the sample having 70% carbon-12 and 30% carbon-14?
- 15
- 16
- 12
- 14
Hint:
The average atomic mass of nitrogen isotope is the percentage present multiplies by that atomic mass of all the isotopes added.
The correct answer is: 14
The average atomic mass of nitrogen isotope is the percentage present multiplies by that atomic mass of all the isotopes added.
The isotopes of carbon are 70% carbon-12 and 30% carbon-14.
The average mass = (0.7 
12 + 0.3 14) = (8.4 + 4.2) = 12.6
Related Questions to study
Chemistry
Calculate the average atomic mass of nitrogen isotope (14N and 15N) present in the atmosphere?
Calculate the average atomic mass of nitrogen isotope (14N and 15N) present in the atmosphere?
ChemistryGrade-9
Chemistry
What is the mass of hydrogen in terms of amu?
What is the mass of hydrogen in terms of amu?
ChemistryGrade-9
Chemistry
Molecular mass is the mass of one molecule of a substance expressed in _________.
Molecular mass is the mass of one molecule of a substance expressed in _________.
ChemistryGrade-9
Chemistry
Gram molecular mass is _________ as the molar mass.
Gram molecular mass is _________ as the molar mass.
ChemistryGrade-9
Chemistry
__________method is used for calculating mass to charge for one or more molecules.
__________method is used for calculating mass to charge for one or more molecules.
ChemistryGrade-9
Chemistry
In which of the following pairs do 1 g of each have an equal number of molecules?
In which of the following pairs do 1 g of each have an equal number of molecules?
ChemistryGrade-9
Chemistry
Mass of H2O in 1000 kg CuSO4 .5H2O is:
Mass of H2O in 1000 kg CuSO4 .5H2O is:
ChemistryGrade-9
Chemistry
Atomic weight is the weight of an atom relative to _______ of weight of 1 atom of C- 12
Atomic weight is the weight of an atom relative to _______ of weight of 1 atom of C- 12
ChemistryGrade-9
Chemistry
Find the total number of iron atoms present in 224 amu iron.
Find the total number of iron atoms present in 224 amu iron.
ChemistryGrade-9
Chemistry
Calculate the total ions & charge present in 4.2 gm of N–3.
Calculate the total ions & charge present in 4.2 gm of N–3.
ChemistryGrade-9
Chemistry
Calculate the following for 49 gm of H2SO4.
Calculate the following for 49 gm of H2SO4.
ChemistryGrade-9
Chemistry
Find the weight of water present in 1.61 g of Na2SO4 .10H2O?
Find the weight of water present in 1.61 g of Na2SO4 .10H2O?
ChemistryGrade-9
Chemistry
Calculate the volume in liters of 20 g hydrogen gas at STP.
Calculate the volume in liters of 20 g hydrogen gas at STP.
ChemistryGrade-9
Chemistry
1 atomic mass unit is equal to
1 atomic mass unit is equal to
ChemistryGrade-9
Chemistry
If water samples are taken from sea, rivers or lakes, they will be found to contain hydrogen and oxygen in the approximate ratio of 1:8. This indicates the law of
If water samples are taken from sea, rivers or lakes, they will be found to contain hydrogen and oxygen in the approximate ratio of 1:8. This indicates the law of
ChemistryGrade-9
