Answer: -
15.55 M
35.325 molal
Explanation: -
Let the volume of the solution be 1000 mL.
Density of nitric acid = 1.42 g/ mL
Total Mass of nitric acid Solution = Volume of nitric acid x Density of nitric acid
= 1000 mL x 1.42 g/ mL
= 1420 g.
Percentage of HNO₃ = 69%
Amount of HNO₃ = 
= 979.8 g
Molar mass of HNO₃ = 1 x 1 + 14 x 1 + 16 x 3 = 63 g /mol
Number of moles of HNO₃ = 
= 15.55 mol
Molarity is defined as number of moles per 1000 mL
We had taken 1000 mL as volume and found it to contain 15.55 moles.
Molarity of HNO₃ = 15.55 M
Mass of water = Total mass of nitric acid solution - mass of nitric acid
= 1420 - 979.8
= 440.2 g
So we see that 440.2 g of water contains 15.55 moles of HNO₃
Molality is defined as number of moles of HNO₃ present per 1000 g of water.
Molality of HNO₃ = 
= 35.325 molal
Answer:
- About 18 g of NH₄Cl will precipitate.
Explanation:
The <em>table G</em> is the graph of the solubility curves for several solutes which is attached.
The second picture identifies the solubilities for the NH₄Cl at 50ºC and 10ºC.
The solubility of NH₄Cl at 50ºC is about 52 g/ 100 g of water.
The solubility of NH₄Cl at 10ºC is about 34 g / 100 g of water.
Then, at 50ºC 100 g of water saturated with NH₄Cl contains about 52 g of NH₄Cl and 100 g of water saturated with NH₄Cl contains 34 g of NH₄Cl.
The difference, 52g - 34 g of NH₄Cl shall precipitate:
52 g - 34 g = 18g ← answer
<h2>Answer:</h2>
Option (B):
The products can form reactants, and the reactants can form products.
<h3>Explanation:</h3><h3>Reversible reaction</h3>
A reversible reaction is a reaction where the reactants form products, which react together to give the reactants back.
aA + bB ⇄ cC + dD
A and B can react to form C and D or, in the reverse reaction, C and D can react to form A and B.
Other options are wrong because off:
(A) Concentration changes with time equilibrium concentration and higher product concentration is also possible.
(C) They may be constant.
(D) Concentration changes with time equilibrium concentration and higher reactant concentration is also possible.
A species with a positive charge will have a net attraction to a species with a negative charge. Among the choices, N3- is the only one attracted to a positive charge.
Number of O atoms : 24
<h3>Further explanation</h3>
Given
C₆H₁₂O₆ compound
Required
Number of atoms
Solution
A molecular formula shows the number of atomic elements in compound.
The empirical formula is the smallest comparison of the atoms
Glucose-C₆H₁₂O₆ is composed of 3 elements, namely C, H, and O.
The number of atoms in a compound can usually be seen from the subscript number after the atom and the reaction coefficient shows the number of molecules
So number of O atoms :
= 4 x 6 = 24 atoms
