...because this notation increases the convenience in using the numbers
Explanation:
Beryllium is a group 2 element and its atomic number is 4. Electronic configuration of beryllium is
.
Since, a beryllium contains two valence electrons so, in order to attain stability it will readily lose its 2 valence electrons.
Therefore, a beryllium atom upon losing two valence electrons will acquire a +2 charge.
Thus, we can conclude that the net ion charge of Beryllium is +2.
Answer:
Similarities: both state the mass of chemical species and they have the same numerical value
Differences: molecular mass refers to one single molecule and molar mass refers to one mole of a molecule
Explanation:
The molecular mass is the value of the mass of each molecule and it is measured in mass units (u). It is calculated adding the mass of each atom of the molecule.
The molar mass is the value of the mass of one mole of molecules, which means the mass of 6.022140857 × 10²³ molecules. The unit is g/mol.
For example, we can consider the methane molecule, which has the chemical formula of CH₄:
Molecular mass CH₄ = C mass + 4 x (H mass)
Molecular mass CH₄ = 12.01 + 4 x (1.01)
Molecular mass CH₄ = 16.05 u
Now to calculate the molar mass we multiply the value of the molecular mass by the Avogadro number and convert the units to g/mol:
Molar mass CH₄: 16.05 x
x 6.022140857 × 10²³ mol⁻¹
Molecular mass CH₄ = 16.05 g / mol
Frequency.
The equation to find the velocity of a wave length is:
v=fλ
V stands for velocity
F stands for frequency
λ stands for wavelength
CH4 + 2 O2 ---> CO2 + 2 H2O Q = 891,6 kJ / mol CH4
1 mol CH4 = 16 g
16 g ---- 891,6 kJ
x g ----- 272 kJ
x = 272 kJ × 16 g / 891,6 kJ = 4,88 g
You must burn 4,88 g of CH4.
:-) ;-)