Answer:
Na₂CO₃•H₂O
Explanation:
After it is heated, the remaining mass is the mass of sodium carbonate.
30.2 g Na₂CO₃
Mass is conserved, so the difference is the mass of the water:
35.4 g − 30.2 g = 5.2 g H₂O
Convert masses to moles:
30.2 g Na₂CO₃ × (1 mol Na₂CO₃ / 106 g Na₂CO₃) = 0.285 mol Na₂CO₃
5.2 g H₂O × (1 mol H₂O / 18.0 g H₂O) = 0.289 mol H₂O
Normalize by dividing by the smallest:
0.285 / 0.285 = 1.00 mol Na₂CO₃
0.289 / 0.285 = 1.01 mol H₂O
The ratio is approximately 1:1. So the formula of the hydrate is Na₂CO₃•H₂O.
This is covalent network type of solid.
For example, silicon dioxide (SiO₂) is covalent network solid with covalent bonding.
Covalent network solid is a chemical compound (or element) in which the atoms are bonded by covalent bonds in a continuous network extending throughout the material.
Silicon(IV) oxide has continuous three-dimensional network of SiO₂ units and diamond has sp3 hybridization.
This solids do not have free electrons so they are good insulators.
They have strong covalent bonds, so they melt at extremely high temperature.
Other examples are quartz, diamond, and silicon carbide.
More about network solid: brainly.com/question/15548648
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Answer:
Reliable knowledge is knowledge that has a high probablility of being true because its veracity has been justified by a reliable method. Reliable knowledge is sometimes called justified true belief, to distinguish reliable knowledge from belief that is false and unjustified or even true but unjustified.
From the equation, we can see that the molar ratio between hydrogen and oxygen is:
2 : 1
Next, we determine the moles of hydrogen and oxygen that are actually present using:
moles = mass / Mr
Hydrogen:
moles = 4 / 2 = 2
Oxygen:
10/32 = 0.3125
Therefore, it is evident that the moles of oxygen present, 0.3125, are less than those that are required for 2 moles of hydrogen, which is 1. This makes oxygen the limiting reactant, which is the one that limits the completion of a reaction.
