The correct answer for the question that is being presented above is this one: "C. planetesimals ® heavier elements ® inner planets ® protoplanets" The list of the stages of development of the inner planets is this <span>C. planetesimals ® heavier elements ® inner planets ® protoplanets</span>
Answer:
[NaOH} = 0.4 M
Explanation:
In a reaction of neutralization, we determine the equivalence point of the titration. In this case, we have a strong base and a strong acid.
(H₂SO₄, is considered strong, but the first deprotonation is weak)
2NaOH + H₂SO₄ → Na₂SO₄ + 2H₂O
As we have 2 protons in the acid, we need 2 OH⁻ from the base to form 2 molecules of water.
In the equivalence point we know mmoles of base = mmoles of acid
Let's finish the excersise with the formula
25 mL . M NaOH = 28.2 mL . 0.355M
M NaOH = (28.2 mL . 0.355M) / 25 mL → 0.400
<u>Answer 2 :</u> The given electronic configuration for a neutral atom of phosphorous in its ground state is incorrect.
Explanation :
A neutral atom of phosphorous has 15 electrons.
The given electronic configuration is incorrect.
The reason is, According to Aufbau principle, the electrons will be first filled in the sub-shell having lower orbital energy. As from the given configuration, 3p sub-shell has lower orbital energy than 4s sub-shell. So, the electrons will be filled in 3p sub-shell first. Hence, the ground state electronic configuration of neutral atom of phosphorous is,
<u>Answer 3 :</u>
Element Rubidium Magnesium Aluminium
Symbol Rb Mg Al
Group number 1 2 13
Number of valence 1 2 3
electrons
The order of general reactivity on the basis of number of valence electrons.
Rb > Mg > Al
Reason : The reactivity is determined by the number of electrons present in the outermost shell that means the element which have 1 valence electron will be more reactive because they can easily lose electrons.