Answer: 770 g water are needed to dissolve 27.8 g of ammonium nitrate
in order to prepare a 0.452 m solution
Explanation:
Molality : It is defined as the number of moles of solute present per kg of solvent
Formula used :

where,
n= moles of solute
Moles of
= weight of the solvent in g = ?


Thus 770 g water are needed to dissolve 27.8 g of ammonium nitrate
in order to prepare a 0.452 m solution
Answer:

Explanation:
1. Calculate the molar mass of N₂H₄
2N = 2 × 14 = 28
4H = 2 × 1 = <u> 4</u>
Tot. = 32
2. Calculate the mass percent of N

<h3>The average atomic mass of Iodine : 126.86 amu</h3><h3>Further explanation</h3>
Given
80% 127I, 17% 126I, and 3% 128I.
Required
The average atomic mass
Solution
The elements in nature have several types of isotopes
Atomic mass is the average atomic mass of all its isotopes
Mass atom X = mass isotope 1 . % + mass isotope 2.% + ... mass isotope n.%
Atomic mass of Iodine = 0.8 x 127 + 0.17 x 126 + 0.03 x 128
Atomic mass of Iodine = 101.6 + 21.42 + 3.84
Atomic mass of Iodine = 126.86 amu
Answer:

Explanation:
Hello.
In this case, since the molecular formula of the given alcohol is C₄H₁₀O (molar mass = 74.14 g/mol), we can write its combustion reaction as shown below:

Thus, since there is a 1:4 mole ratio with carbon dioxide (molar mass = 44..01 g/mol) and a 1:5 mole ratio with water (molar mass = 18.02 g/mol), we can compute the obtained masses as shown below:

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