Answer:
Model A
Explanation:
Model A represents an atom that is more reactive than the others represented.
Valence electrons actually determine the reactivity of elements. They also determine the properties of elements.
Elements with one valence electron are highly reactive because they need low energy to remove them. They can either gain more electrons to become stable or they share/give out their electrons.
Therefore, Model A is the correct answer because it has one valence electron and its valence electron is farther from the nucleus thereby this makes it more reactive.
There are no above options to choose from so I am giving an example of a X3Y2 formula which is Magnesium nitride, the formula is Mg3N2.
Answer:
NaOH
Explanation:
Look at charge Na has +1 charge and Ca has +2 charge after dissociation . Greater charge Stronger lattice. And as we need weak Lattice, so NaoH is stronger base than Ca(OH)2.
Answer:
the mass of 2.9 moles of calcium is 116 g
Explanation:
The computation of the mass of 2.9 moles of calcium is shown below
As we know that
Mole = mass ÷ molar mass
where,
Moles be 2.9
And, we know that the molar mass of calcium be 40g/mol
Now put the values to the above formula
2.9 = Mass ÷ 40
So, the mass would be
= 40 × 2.9
= 116 g
Hence, the mass of 2.9 moles of calcium is 116 g