Answer:
0.416666667
Explanation:
number of moles= mass of sample ÷ molar mass
=5÷12
=0.41666667
Answer:
What is most widely accepted today is the giant-impact theory. It proposes that the Moon formed during a collision between the Earth and another small planet, about the size of Mars. The debris from this impact collected in an orbit around Earth to form the Moon.
Explanation:
Answer:
49.86 × 10²³ atoms of Al
Explanation:
Given data:
Number of moles of Al = 8.28 mol
Number of atoms = ?
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,
18 g of water = 1 mole = 6.022 × 10²³ molecules of water
1.008 g of hydrogen = 1 mole = 6.022 × 10²³ atoms of hydrogen
For 8.28 moles of Al:
1 mole = 6.022 × 10²³ atoms of Al
8.28 mol×6.022 × 10²³ atoms / 1mol
49.86 × 10²³ atoms of Al
The element in period 4 of the Periodic Table with the highest electronegativity is krypton (2.96).
It's A.
Chemical properties cannot be determined by viewing or touching substance, and physical properties can be measured without changing the composition of matter:)
