When looking down the groups the elements have an equal number of electrons in the outer shell. This means they react in a similar way making it easier for scientists to use.
Answer: number of atoms is 5.21 · 10^24
Explanation: Atomic mass of Be is 9.012 g/mol.
Number of moles n = m/M = 78.0 g / 9.012 g/mol =
Multiply this with Avogadro number Na = 6.022*10^23 1/mol
To fill the other element's shell.
Answer:
375 mL
Explanation:
M1*V1 = M2*V2
M1 = 1.00 M
V1 = ?
M2 = 0.750 M
V2 = 0.500 L
1.00 M * V1 = 0.750 M * 0.500 L
V1 = 0.750*0.500/1.00 = 0.375 L = 375 mL