Answers:
Atomic number = 63
Mass = 150.919 a.m.u
Nuclear symbol = ¹⁵¹Eu₆₃
Explanation:
Europium (Eu) is a member of lanthanide series in periodic table. these are radioactive elements that emits radiations continuously. these elements are also called rare earth element due to their rare existent.
Europium (Eu) has two naturally occurring isotopes as follow,
1) Eu¹⁵² with 52.19 % abundance.
2) Eu¹⁵¹ with 47.81 % abundance.
I think all of them are accurate, you can also search each one of them on the internet
Note: Above question is incomplete: Complete question is read as
<span>According the the arrhenius theory, which species does an acid produce in an aqueous solution?
</span>A) hydrogen ions B) hydroxyl ions C) Sodium ions D) Chloride ion
.....................................................................................................................
Correct answer for above question is A) Hydrogen ions
Reason:
According the Arrhenius theory of acid and base, acid generates hydrogen ions in aqueous medium, while bases generates hydroxyl ions in aqueous medium.
Example of Acid:
HCl(aq) → H+(aq) + Cl-(aq)
Example of Base:
NaOH(aq) → Na+(aq) + OH-(aq)
Answer:
84.259 kPa
Explanation:
We know that:
1 kPa is approximately equal to 7.5 mmHg
Therefore, to convert 632 mmHg to kPa, we will simply use cross multiplication as follows:
1 kPa .................> 7.5006 mmHg
?? kPa ................> 632 mmHg
632 mmHg = (632*1) / (7.5006) = 84.259 kPa
Hope this helps :)
