Answer:
a, d and e. are true.
Explanation:
The reaction that occurs is:
Na2CO3(aq) + CaCl2(aq) → CaCO3(s) + 2NaCl
In ideal conditions, the percent yield of the reaction must be 100%. All explanations about why the student could not collect all precipitate are right:
a. The combined reactants were not stirred before filtering the precipitate. Not stirring could not promote all the reaction. <em>TRUE.</em>
b. The student did not completely dry the precipitate before weighing it. If the student don't dry the precipitate, the mass of precipitate must be higher producing a percent yield > 100%. <em>FALSE.</em>
c. The precipitate was not washed prior to drying. Produce more mass. <em>FALSE.</em>
d. A rubber policeman was not used to scrape precipitate from the beaker. If the student doesn't collect all the precipitate the percent yield could be < 100%.. <em>TRUE.</em>
e. The filter paper was not wetted with water prior to filtering the precipitate. <em>TRUE. </em>If you don't wet the filter paper you can lose a part of precipitate from the walls of this one.
Answer:
Susan is right
Explanation:
Honey is a natural substance extracted from bees. Like every other natural substance, honey is a mixture of many different substances. An analysis of the so called 'pure honey' will reveal that many chemical species compose the natural substance called honey.
Hence Susan is right when she says that honey is not really pure but a mixture of substances.
The distance covered by each atom of copper will be twice the radius of each atom, which is its diameter
it will be like as shown in diagram....
Let the number of atoms required is "n"
thus total atoms required will be
Let us convert pm to mm for unit cancellation.
Thus
hence
The following substance must be an A. Compound.