When an electron drops from one level to a lower energy level, it emits a quantum of energy. The different mix of energy differences for each atom produces different colours. Each metal gives a characteristic flame emission spectrum.
In the periodic table, elements of the same group are characterized by having the same similar properties.
So, first we will check the elements that lie within the same group as <span>beryllium and then we will attempt to choose the elements with atomic mass higher than 130.
So, elements in the same group as </span>beryllium are: magnesium, calcium, strontium, barium and radium.
Among these elements, we will find that:
radium has atomic mass of 226 amu
barium has atomic mass of 137.327 amu
Based on this, the two elements would be barium and radium.
Answer:
a) E = 17.55 MeV
b) E = 18.99 MeV
c) E = 3.29 MeV
d) You can use the methods applied for the other parts to solve this, the equation is not properly written
e) E = 4.075 MeV
Explanation:
Energy Released, 

Mass of 1H, 
Mass of 2H, 
Mass of 3H, 
Mass of Helium, 
Mass of Beryllium, 
Mass of neutron, 
a) 

Energy released,

Energy released = 17.55 MeV
b) 

Energy released,

c)
+ n

Energy released,

E = 3.29 MeV(Energy is released)
d) You can use the methods applied for the other parts to solve this, the equation is not properly written
e) 


E = 4.075 MeV ( Energy is released)
Answer:
0.095M
Explanation:
HClO4 + NaOH = NaClO4 + H2O
Concentration of acid CA= 0.170M
Concentration of base CB= ???
Volume of base VB= 28.5ml
Volume of acid VA= 16.0ml
Number of moles of acid nA= 1
Number of moles of base nB= 1
From
CAVA/CBVB= nA/nB
CB= CAVAnB/VBnA
CB= 0.170×16.0×1/28.5×1
CB= 0.095M