2 floors because they are double the work.
The a answer to the statement is between B and D
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.
The balanced equation is:
BaCl2 (aq) + Na2SO4 (aq) ----> BaSO4(s)+ 2 NaCl(aq)
This is a double replacement reaction.
The reactants are:
a) BaCl2: barium chloride, a ionic compound, therefore soluble in water,
b) Na2SO4: sodium sulfate, another ionic compound, therefore also soluble in water.
The products are:
c) BaSO4: barium sulfate, a solid not soluble in water which precipitates.
d) NaCl: sodium chloride, an ionic compound, therefore soluble in water.
Because the Earth<span> is a sphere, the surface gets much more intense sunlight, hence heat, at the equator than at the poles.</span>
The distribution of heat around the globe, and through the year, coupled with the physical properties of air, produce a distinctive pattern of climatic zones.