N2 + 3H2 ---> 2NH3
nitrogen + hydrogen ---> ammonia
Answer: A.
fossil
B.
rock layer
Explanation:
Relative aging or dating can be define as the technique for determination of the age of the rock and fossil. It is a method of determining the chronological order of the past events by comparing the stratigraphic column of rocks and sediments with each other. This method can only give relative age of one object in comparison with the other but does not give the absolute date.
Citric acid has the molecular formula C6H8O7 so you can add the molar masses of the elements from the periodic table. C has a molar mass of 12.01 g/mol, H has 1.01 g/mol and O has 15.999 g/mol. Now you calculate the total molar mass= (6*12.01 + 8*1.01 + 7*15.999). This yields a molar weight of 192.124 g/mol (anhydrous)
