Answer: Answer:
"The arrangement of atoms or ions in a crystal " is described by the terms body-centered cubic and face-centered cubic.
Explanation:
Face centred cubic system explains the crystal structure where an atom is present at each cubic corner of the crystal and the centre of each cube face. Meaningfully, a closed packed plane where at each "face of the cube" atoms touch the alongside face diagonals.
Whereas in body centric cube system has the lattice point present at the 8 corners of cell and an additional one at the center of the cell. Thus, both explains how the atom or ions are placed or arranged in a crystal.
Explanation: Hope this helps :)
Answer:
B.Convection
the movement caused within a fluid by the tendency of hotter and therefore less dense material to rise, and colder, denser material to sink under the influence of gravity, which consequently results in transfer of heat.
the semipermeable membrane surrounding the cytoplasm of a cell.
Answer:
4.5 × 10²³ number of atoms Al
Explanation:
Given data:
Mass of Al = 20 g
Number of atoms of Al = ?
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.
We will calculate the number of moles of Al first:
Number of moles = mass/molar mass
Number of moles = 20 g/ 27 g/mol
Number of moles = 0.74 mol
1 mole = 6.022 × 10²³ number of atoms
0.74 mol × 6.022 × 10²³ number of atoms / 1 mol
4.5 × 10²³ number of atoms Al