6.4 * 6.02 * 10^23 = 3.8528*10^24 atoms
Don't let the fact that it's vanadium throw you off, avagadros constant stays the same for all elements
Explanation:
To delineate the the nature of the bonds that would be formed between the two elements, let us first write the electronic configuration of the two species;
Be = 2, 2
F = 2, 7
Beryllium is a metal with two valence electrons whereas fluorine is a halogen with seven valence electrons.
When Be loses two electrons it becomes isoelectronic with He;
Be → Be²⁺ + 2e⁻
Also, when fluorine gains an electron, it becomes isoelectronic with Ne;
F + e⁻ → F⁻
This loss and gain of electrons between the two elements creates an electrostatic attraction them and they enter into an electrovalent bond.
Hence;
Be²⁺ + 2F⁻ → BeF₂
Answer:
0.45 g
Explanation:
Step 1: Given data
- Molar mass of methionine (M): 149.21 g/mol
- Volume of the solution (V): 20 mL
- Concentration of the solution (C): 150 mM
Step 2: Calculate the moles of methionine (n)
We will use the following expression.
n = C × V
n = 150 × 10⁻³ mol/L × 20 × 10⁻³ L
n = 3.0 × 10⁻³ mol
Step 3: Calculate the mass of methionine (m)
We will use the following expression.
m = n × M
m = 3.0 × 10⁻³ mol × 149.21 g/mol
m = 0.45 g
A mole contains Avogadro’s number of particles of a substance.
No I can’t
EXAMPLE took the test k12
