Concept explainers
(a)
Interpretation:
Whether the statement-Formula weight is the mass of a compound expressed in grams, is true or false should be determined.
Concept Introduction:
Formula mass is the sum of masses of the atoms present in a molecule. These compounds are those that do not generally occur as a single molecule. e.g.
When we calculate the sum of masses of the elements present in a compound in 1 mole, we calculate it for the
For example:
Answer to Problem 25P
Formula weight is the mass of a compound expressed in amu.
Explanation of Solution
The statement- Formula weight is the mass of a compound expressed in grams is false.
Formula mass is the sum of masses of the atoms present in a molecule. These compounds are those that do not generally occur as a single molecule. e.g.
When we calculate the sum of masses of the elements present in a compound in 1 mole, we calculate it for the Avogadro number, molar mass comes out in grams.
For example:
(b)
Interpretation:
To determine whether the statement-1
Concept Introduction:
The unit amu is used to express mss of an element in grams. It is 1/12th of mass of 1 atom of C-12.
When this is calculated for 1 mole we multiply it with the Avogadro number.
Answer to Problem 25P
1 atomic mass unit (u) is not equal to 1 gram(g).
Explanation of Solution
The statement- 1 atomic mass unit (u) is equal to 1 gram(g) is false.
The unit amu is used to express mss of an element in grams. It is 1/12th of mass of 1 atom of C-12.
When this is calculated for 1 mole we multiply it with the Avogadro number.
If we calculate mass of 1 atom of Hydrogen.
If we calculate mass of 1 mole of Hydrogen.
(c)
Interpretation:
To determine whether the statement-Formula weight of
Concept Introduction:
Formula mass is the sum of masses of the atoms present in a molecule. These compounds are those that do not generally occur as a single molecule. e.g.
When we calculate the sum of masses of the elements present in a compound in 1 mole, we calculate it for the Avogadro number, molar mass comes out in grams.
For example:
Answer to Problem 25P
Formula weight of
Explanation of Solution
The statement- Formula weight of
Formula mass is the sum of masses of the atoms present in a molecule. These compounds are those that do not generally occur as a single molecule.e.g.
When we calculate the sum of masses of the elements present in a compound in 1 mole, we calculate it for the Avogadro number, molar mass comes out in grams.
E.g -
(d)
Interpretation:
To determine whether the statement-Molecular weight of
Concept Introduction:
Molecular weight is the sum of masses of the atoms present in a molecule.
When we calculate the sum of masses of the elements present in a compound in 1 mole, we calculate it for the Avogadro number, molar mass comes out in grams.
Answer to Problem 25P
Molecular weight of
Explanation of Solution
The statement-Molecular weight of
Molecular weight is the sum of masses of the atoms present in a molecule.
When we calculate the sum of masses of the elements present in a compound in 1 mole, we calculate it for the Avogadro number, molar mass comes out in grams.
E.g -
(e)
Interpretation:
To determine whether the statement-The molecular weight of a covalent compound is the same as its formula weight., is true or false.
Concept Introduction:
Formula weight is the sum of masses of the atoms present in a molecule.
Molecular weight is the sum of masses of the atoms present in a molecule.
When we calculate the sum of masses of the elements present in a compound in 1 mole, we calculate it for the Avogadro number, molar mass comes out in grams.
Answer to Problem 25P
The molecular weight of a covalent compound is the same as its formula weight.
Explanation of Solution
The statement-The molecular weight of a covalent compound is the same as its formula weight. is true.
Molecular weight is the sum of masses of the atoms present in a molecule.
Formula weight is the sum of masses of the atoms present in a molecule.
Molecular weight is the sum of masses of the atoms present in a molecule.
Formula weight is the sum of masses of the atoms present in a molecule.
When we calculate the sum of masses of the elements present in a compound in 1 mole, we calculate it for the Avogadro number, molar mass comes out in grams.
E.g -
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Chapter 4 Solutions
INTRO.TO GENERAL,ORGANIC+BIOCHEM.(LL)
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