Answer:
ΔS° = - 47.2 J/mol.K
Explanation:
ΔS°= 4(S°mH3PO4) - 6(S°mH2O) - S°mP4O10
∴ S°mH2O(l) = 69.9 J/mol.K
∴ S°mP4O10 = 231 J/mol.K
∴ S°mH3PO4 = 150.8 J/mol.K
⇒ ΔS° = 4*(150.8) - 6*(69.9) - 231
⇒ ΔS° = - 47.2 J/mol.K
Answer:
Bombardment by asteroids
Explanation:
All of the other ones explain themselves
Answer: The metal that has a greater reactivity is more easily oxidized.
Explanation:
Oxidation is when the elements lose electrons and increase their oxidation state.
The metals tend to react by losing electrons and form the corresponding cation.
For expample, sodium (an alkalyne metal) loses one elecron and form the cation Na¹⁺ , then this cation combine with an anion and form compounds like NaCl, NaOH. The same do the other alkalyne metals.
Magnesium (an alkalyne earth metal) loses two electrons and form the cation Mg²⁺, then it combines with some anions to form compounds, like MgSO₄, Mg(OH)₂.
So, the easier the metal gets oxidized the greater its reactivity.
Answer:
Element symbol: Kr.
Mass number: 77.
Charge : 0.
Explanation:
Hello,
In this case, since such substance has the same amount of protons and electrons we can infer it is an atom whose number of neutrons is defined by considering its atomic mass or mass number and atomic number which is actually equal to the number of protons and electrons (36):

In such a way, solving for the atomic mass we obtain:

It means that the element is krypton (Kr) as it has 36 electrons and protons so its charge is 0.
Best regards.
Answer: A volume of 455 mL from 0.550 M KBr solution can be made from 100.0 mL of 2.50 M KBr.
Explanation:
Given:
= ?,
= 0.55 M
= 100.0 mL,
= 2.50 M
Formula used to calculate the volume of KBr is as follows.

Substitute the values into above formula as follows.

Thus, we can conclude that a volume of 455 mL from 0.550 M KBr solution can be made from 100.0 mL of 2.50 M KBr.