Relative molecular mass or RMM is the answer.
Explanation:
After the electron configuration, the last shell of the beryllium atom has two electrons. In this case, both the valence and valence electrons of beryllium are 2. We know the details about this. The elements that have 1, 2, or 3 electrons in the last shell donate the electrons in the last shell during bond formation.
Answer:
Pressure gas A
using boyles law

=
V2
V2 = 717ml + 179 ml
= 896ml
∴
= 2.50 × 717ml/896ml
= 2.0 bar
Pressure B
P2 = 4.30 bar× 179ml/896ml
= 0.859bar
ptotal =
+
= 2.0 bar + 0.859 bar
= 2.859 bar
Explanation: Using Daltons law of partial pressure,the pressure is independently of each other when the gas is exerted.where we can use daltons law to find the pressure of each gas separately when it expands into the total volume in two containers.
Answer:
a. Each set of elements was arranged in special coloumns based on their mass.