hydrogen is the lightest element in the periodic table
Mass C₆H₈O₇ : 0.531484 g
<h3>Further explanation</h3>
Reaction
3NaHCO₃ (aq) + C₆H₈O₇ (aq) → 3 CO₂ (g) + 3 H₂O (l) + Na₃C₆H₅O₇ (aq)
MW NaHCO₃ : 84 g/mol
mass NaHCO₃ : 7.10² mg=0.7 g
mol NaHCO₃ :

mol C₆H₈O₇ :

MW C₆H₈O₇ : 192 g/mol
mass C₆H₈O₇ :

The molality is 0.54 M when 1.34 moles of NaCl is present in 2.47 kg of solvent.
<u>Explanation:</u>
Molality is the measure of how much of amount of solute is dissolved in the solvent. So it is calculated as the ratio of moles of solute to the grams of solvent.

As in this case, the solute is NaCl and solvent is unknown. So the moles of solute is given as 1.34 moles and the mass of solvent is given as 2.47 kg.
Hence, 
Thus, the molality is 0.54 M when 1.34 moles of NaCl is present in 2.47 kg of solvent.
Answer:
The complete question is as follows
Given the incomplete equation: 2 N2O5(g) ==> Which set of products completes and balances the incomplete equation?
A)2 N2(g) + 3 H2(g)
B)2 N2(g) + 2 O2(g)
C)4 NO2(g) + O2(g)
D)4 NO(g) + SO2(g)
The correct option is C) 4NO2(g) + O2(g)
Explanation:
Note that the products should be NO2 and O2 since the reactant is entirely made up of N and O. option A is not correct as hydrogen cannot emerge as a product in this reaction. Matter can never be created or be destroyed bu can only change in a chemical reaction. Option D is not also correct for the same reason.
Option B is not correct since it did not balance the number of atoms of O and N in the reactant side of the equation.
The option C) 4NO2(g) + O2(g) is therefore the right option since it balances both the elements and the number of atoms of the elements present.
Answer: the new force will be 1/9 of the original force
Explanation: Please see attachment for explanation