Answer:
A.) 34.866 x 10¯23 g/atom
B.) 2.64 x 10^22 atoms in 1 cm3
C.) 1 atoms per unit cell
Explanation:
A) Calculate the average mass of one atom of polonium:
210g mol¯1 ÷ 6.022 x 1023 atoms mol¯1 = 34.866 x 10¯23 g/atom
B) Determine atoms in 1 cm3:
9.19g / 34.866x 10¯23 g/atom = 2.64 x 10^22 atoms in 1 cm3
Determine volume of the unit cell:
(3.37 x 10¯8 cm)3 = 3.827 x 10¯23 cm3
Determine number of unit cells in 1 cm3:
1 cm3 / 3.827 x 10¯23 cm3 = 2.61 x 1022 unit cells
C) Determine atoms per unit cell:
2.64 x 1022 atoms / 2.61 x 1022 unit cells = 1 atoms per unit cell
Cl2(s); oxidation number 1 is the incorrect choices in oxidation number.
Explanation:
In the elemental form oxidation state is zero. Here chlorine is present in elemental form so oxidation state is zero.
Oxidation number depends on the number of electrons gained or lost by an atom of the element say in compound formation.
If electron is gained oxidation number becomes negative.
If electron is lost then oxidation number is positive.
If the octet rule is fulfilled that valence shell is filled them atomic number gets zero. Since Cl2 is in neutral state the oxidation number is 0.
Oxidation number in general can be made out by checking the valency of the element as oxidation number is also equal to the valency.
Answer:
Melamine is used for making tableware,cooking utensils, plates, plastic products etc.
Explanation:
Melamine is used to manufacture many products. How? Well melamine-formaldehyde resin, as it's full name, forms molecular structures that are molded, with heat, to take the shape of the items such as tableware.
After this chemical reaction takes place, the "left over" remains as plastic.
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And so, it is used in products such as cooking utensils, plates, plastic products etc.
Answer:
Explanation:
*Since the titration is between the strong acid HCl and the strong base Ca(OH)2, the pH at the equivalent point should be 7. On interpolation, we will obtain that 9.50mL and 9.82 mL of HCl is required to completely neutralized the given Ca(OH)2 solution.
*pH at the equivalence point =7
we know that pH + pOH = 14
Hence pOH= 14-7=7
pOH= -log(OH-)
The concentration of OH-= 10-pH= 1X10-7 M
One reason for the low solubility may be the higher reaction temperature, Another reason is the common ion effect.
The answer is <span>The mass of sodium chloride formed is less than 76 grams.
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Remember Mass is never gained or loss in any chemical reactions
So,
hydrochloric acid + sodium hydroxide => <span>sodium chloride + water
Total 76 gram Total will also 76 gram
In this case, the mass of sodium chloride will be less than 76 gram because we need to take out the mass of the water.
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