Answer:
Mass = 55.52 g
Explanation:
Given data:
Number of atoms of Li = 4.81×10²⁴ atom
Number of grams = ?
Solution:
The given problem will solve by using Avogadro number.
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.
The number 6.022 × 10²³ is called Avogadro number.
For example,
1.008 g of hydrogen = 1 mole = 6.022 × 10²³ atoms of hydrogen
For Li:
4.81×10²⁴ atom × 1 mol / 6.022 × 10²³ atom
8 moles
Mass in gram:
Mass = number of moles × molar mass
Mass = 8 mol × 6.94 g/mol
Mass = 55.52 g
The smallest participle of an element is called an atom
The correct answer is D. A solid has a high to very high melting point, great hardness , and poor electrical conduction, this is a covalent network solid. This is because of the large amount of energy required to break these bonds, the said properties are exhibited by these solids.
For any given element the mass number can be found by adding the protons and the neutrons.
In this case its 10 protons plus 11 neutrons which gives us 21 as the mass number.