Question

Number of atoms in 20g \[Ca\] is equal to number of molecules in:
A. \[20\,g\,Mg\]
B. \[8\,g\,C{{H}_{4}}\]
C. \[1.8\,g\,{{H}_{2}}O\]
D. \[1.7\,g\,N{{H}_{3}}\]

Answer 1

Hint:A mole is characterized as the mass of the substance which consists of the equivalent amount of essential units. Example- atoms in 12 grams are equivalent to 12C. The basic units can be molecules, atoms or formula units dependent on the substance.

Complete answer:
A mole fraction shows the number of chemical elements. One mole of any substance is equivalent to the estimation of \[6.023\times 10^{23}\] (Avogadro’s number). It very well may be utilized to quantify the products obtained from the chemical reaction. The unit is indicated by mol.
20 grams of calcium (\[20\,g\,Ca\]) is \[0.5mol\]
Option 1st: 20 grams of magnesium (\[20\,g\,Mg\] ) is \[0.83\,mol\]
Option 2nd: 8 grams of methane (\[8\,g\,C{{H}_{4}}\]) is \[0.5\,mol\]
Option 3rd: 1.8 grams of water (\[1.8\,g\,{{H}_{2}}O\]) is \[0.1\,mol\]
Option 4th: 1.7 grams of ammonia (\[1.7\,g\,N{{H}_{3}}\]) is \[0.1\,mol\]
The Number of atoms in 20 grams of calcium is equal to 8 grams of methane.

Hence, the correct option is B.

Additional Information:
The mole permits an extension between the impossible world of enormous numbers of tiny molecules and having the option to really weigh substances out and work with them. A mole of a substance contains \[6.023\times 10^{23}\] particles of that substance. This is called Avogadro's number.

Note:
The connection among moles and mass is known as molar mass or the number of grams in a single mole of a substance. The molar mass for any element can be found under the symbol on the periodic table.