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
Answer:
the amount of valence electron, cna be found in the periodic table, which is called the atomic number which is top of the symbol
hope this helps!!! best fo luck to you
Answer:
Explanation:
Information given about the element:
Number of protons = 74
Number of neutrons = 110
For the atomic number:
Neutral atoms such as this one would have their atomic number to be the same with their number of electrons and protons:
atomic number = number of protons = number of electrons
The atomic number would therefore be 74
For the mass number:
The mass of an atom is centrally concentrated within the tiny nucleus. The mass number is the sum of protons and neutrons in an atom. Protons and neutrons are nuclear particles and are called nucleons:
Mass number = number of protons + number of neutrons = 74+110=184
Is this a new element?
From the peroidic table, tungsten(W) perfectly fits this description of the atom. It has an atomic number of 74 and a mass number of approximately 184. The element is not a new element.
Is it solid, liquid, or gas?
The element is a hard metallic solid. It is a classified as a transition metal on the periodic table. Transition metals have very unique metals and are mostly solids.
(H+)(OH-) = Kw
kw= 1 x10^-14
OH-= 1 x10 ^-11
(H+)= KW / OH-
concentration of H+ = (1x10^-14) /.(1 x 10 ^-11) = 1 x10 ^-3
Ph= -log (H+)
PH=-log ( 1 x 10 ^-3) = 3 therefore the solution is acidic since the PH less than 7
