Question

Oxygen occurs in nature as a mixture of isotopes $$^{16}O{,^{17}}O$$   and $$^{18}O$$  having atomic masses of $$15.995\,u,16.999\,u$$     and $$17.999\,u$$   and relative abundance of $$99.763\% ,0.037\% $$     and $$0.200\% $$   respectively. What is the average atomic mass of oxygen ?

A. 15.999$$\,u$$  
B. 16.999$$\,u$$
C. 17.999$$\,u$$
D. 18.999$$\,u$$
Answer :   15.999$$\,u$$
Solution :
$$\eqalign{ & {\text{Average atomic mass of oxygen}} \cr & = \frac{{\left( {99.763 \times 15.995} \right) + \left( {0.037 \times 16.999} \right) + \left( {0.200 \times 17.999} \right)}}{{100}} \cr & = 15.999\,u \cr} $$

Releted MCQ Question on
Physical Chemistry >> Some Basic Concepts in Chemistry

Releted Question 1

$$27 g$$  of $$Al$$  will react completely with how many grams of oxygen?

A. $$8\,g$$
B. $$16\,g$$
C. $$32\,g$$
D. $$24\,g$$
View Answer
Releted Question 2

A compound was found to contain nitrogen and oxygen in the ratio $$28 gm$$  and $$80 gm$$  respectively. The formula of compound is

A. $$NO$$
B. $${N_2}{O_3}$$
C. $${N_2}{O_5}$$
D. $${N_2}{O_4}$$
View Answer
Releted Question 3

The largest number of molecules is in

A. $$36\,g$$  of water
B. $$28\,g$$  of carbon monoxide
C. $$46\,g$$  of ethyl alcohol
D. $$54\,g$$  of nitrogen pentoxide
View Answer
Releted Question 4

The total number of electrons in one molecule of carbon dioxide is

A. 22
B. 44
C. 66
D. 88
View Answer

Practice More Releted MCQ Question on
Some Basic Concepts in Chemistry

Practice More MCQ Question on Chemistry Section

Physical ChemistrySome Basic Concepts in ChemistryStoichiometryStates of Matter Solid, Liquid and GasAtomic StructureChemical ThermodynamicsSolutionsSolid StateSurface ChemistryChemical EquilibriumIonic EquilibriumChemical KineticsRedox ReactionElectrochemistryNuclear Chemistry
Inorganic ChemistryChemical Bonding and Molecular StructureOres and MetallurgyClassification of Elements and Periodicity in PropertiesHydrogenS - Block ElementsP - Block ElementsD and F Block ElementsCo - ordination CompoundsQualitative AnalysisPreparation and Properties of CompoundsEnvironmental Chemistry
Organic ChemistryGeneral Organic ChemistryIsomerismPurification and Characterisation of Organic CompoundsHydrocarbons (Alkane, Alkene and Alkyne)Aromatic hydrocarbonElectrophilic Aromatic Substitution (Haloalkanes and Haloarenes)Alkyl and Aryl HalideReactions on BenzeneAlcohol, Phenol and EtherAldehyde and KetoneCarboxylic AcidOrganic Compounds Containing NitrogenName ReactionsPolymersBiomoleculesChemistry in Everyday LifePractical Organic Chemistry