Explanation:
If a sample is impure, it means it contains multiple substances, this means that when you test it in a flame test, it will come up with a mixed color meaning you wont be able to tell what ions are in the substance.
Biuret reagent will indicate the presence of protein in a given sample. It is also known as the Piotrowski's test. This reagent consists of copper (II) sulfate and sodium hydroxide. It detects peptide bonds by the reaction of the copper ions in an alkaline solution. The copper ions would form violet colored complexes when peptide is present in the solution. From this test, concentration can be calculated since the intensity of the color depends on the amount of peptide bonds and according to the Beer-Lambert law concentration and the absorption of light is proportional. The concentration is calculated by a spectrophotometric technique at a wavelength of 540 nm.
His measurements are precise since his pH values are close to each other in a way that it was repeated in all measurements. On the contrary to accuracy, it is the closeness to the actual pH value he should have achieved. Therefore, Jose's results are precise but not accurate since his value is not close to the actual value of pH 4.
Answer:
Explanation:
Ionic (or electrovalent) compounds conduct electricity when there they are in the aqueous state/solution because the charges of ions of these compounds are what carry the electric charges in the aqueous solution as a result of free movement within the aqueous solution which they do not "have" when in there solid state (where they have a highly restricted movement/compacted structure).
Answer:

Explanation:
1. Calculate the adult life
If the elephant is an adult from its 10th birthday until the day before its 56th birthday, its
Adult life = 55 - 10 + 1 = 46 yr
2. Convert years to days

3. Convert days to pounds of feed

4. Convert pounds to kilograms and megagrams

Note: The answer can have only two significant figures because that is all you gave for age of the elephant.