Answer:
2.05mg Fe/ g sample
Explanation:
In all chemical extractions you lose analyte. Recovery standards are a way to know how many analyte you lose.
In the problem you recover 3.5mg Fe / 1.0101g sample: <em>3.465mg Fe / g sample. </em>As real concentration of the standard is 4.0 mg / g of sample the percent of recovery extraction is:
3.465 / 4×100 = <em>86,6%</em>
As the recovery of your sample was 1.7mg Fe / 0.9582g, the Iron present in your sample is:
1.7mg Fe / 0.9582g sample× (100/86.6) = <em>2.05mg Fe / g sample</em>
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I hope it helps!
A reaction between to acids
The given question is incomplete. The complete question is:
Which is true of Elements on a periodic table in the same group (family)?
A; Elements in the same family have similar chemical properties because they have the same number of electron shells.
B; Elements in the same family have similar chemical properties because they have the same number of valence electrons.
C; Elements in the same family have few similar properties as they have different numbers of electron shells.
D; Elements in the same family are always the same type of Elements and have the same number of protons.
Answer: B; Elements in the same family have similar chemical properties because they have the same number of valence electrons.
Explanation:
Elements are distributed in groups and periods in a periodic table.
Elements that belong to same groups will show similar chemical properties because they have same number of valence electrons.
The chemical reactivity of elements is governed by the valence electrons present in the element.
Example: Flourine, chlorine and bromine are elements which belong to Group 17. They have 9, 17 and 35 electrons respectively and contain 7 valence electrons each and need one electron to complete their octet.
Metals :-
Group 1A - Alkali metals ( highly reactive metals)
Non-metals :-
Group 17 - Halogens ( highly reactive non-metals )
