The model of the atom has dramatically changed over many many years.We learned atoms make up different substances and are the smallest particles of matter, which have subatomic particles that are very small portions of matter. At first scientist only thought there were electrons which are negatively charged.
Answer is: a. Rubidium (Rb) is more reactive than strontium (Sr) because strontium atoms must lose more electrons.
The ionization energy (Ei) is the minimum amount of energy required to remove the valence electron, when element lose electrons, oxidation number of element grows (oxidation process).
Alkaline metals (group 1), in this example rubidium, have lowest ionizations energy and easy remove valence electrons (one electron), they are most reactive metals.
Earth alkaline metals (group 2), in this example strontium, have higher ionization energy than alkaline metals, because they have two valence electrons, they are less reactive.
Rubidium electron configuration: ₃₇Rb 1s²2s²2p⁶3s²3p⁶3d¹⁰4s²4p⁶5s¹; one valence electron is 5s¹ orbital.
Strontium electron configuration: ₃₈Sr 1s²2s²2p⁶3s²3p⁶3d¹⁰4s²4p⁶5s²; two valence electrons is 5s² orbital.
Heat would be required : 1,670 J
<h3>Further explanation</h3>
Given
mass of H₂O=5 g
Required
Heat to melt
Solution
The heat to change the phase can be formulated :
Q = m.Lf (melting/freezing)
Lf=latent heat of fusion
The heat of fusion for water at 0 °C : 334 J/g
Input given values in formula :
Answer:
Explanation:
The instantaneous speed is the speed of an object at a particular moment in time. And if you include the direction with that speed, you get the instantaneous velocity.
2ZnS(s)+3O2(g) -> 2Zns(s) + 2SO3(g)
the above given equation is unbalanced as it contains 4 moles of sulphur in the output but in the input there are only two aoms of sulphur so to balance the equation we will write the equation as given under
balanced equation is
2ZnS(s)+3O2(g) -> 2Zn(s) + 2SO3(g)
In words:
When 2 moles of solid zinc sulfide reacts with 3 moles of oxygen gas gives 2 moles of solid zinc and 2 moles of sulphur trioxide gas.
