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>
<em></em>
I hope it helps!
Answer:
Compound
Explanation:
We want to know if it's a compound or a mixture.
An example of a mixture is salt water: you can heat it hot enough to boil off the water, leaving only the salt. This is a physical change, which is how you know it's a mixture.
Something like gold is a compound: if you heat it, or hit it, you'll still only have gold. You can only break it down by chemical means, which is how you know it's a compound.
Answer:
C
Explanation:
Melting point, temperature at which the solid and liquid forms of a pure substance can exist in equilibrium. As heat is applied to a solid, its temperature will increase until the melting point is reached. More heat then will convert the solid into a liquid with no temperature change.
