Answer:
vacuum
Explanation:
vacuum is the form by which matter cant exist
Empirical formula is the simplest ratio of whole numbers of components in a compound
calculating for 100 g of compound
C H O
mass 64.27 g 7.19 g 28.54 g
number of moles 64.27 g / 12 g/mol 7.19 g/1 g/mol 28.54 g / 16 g/mol
= 5.356 mol = 7.19 mol = 1.784 mol
divide by least number of moles
5.356 / 1.784 7.19 / 1.784 1.784 / 1.784
= 3.002 4.03 = 1.000
rounded off to nearest whole number
C - 3
H - 4
O - 1
empirical formula - C₃H₄O
mass of empirical formula = 12 g/mol x 3 + 1 g/mol x 4 + 16 g/mol x 1 = 56 g
molecular mass = 168.19 g/mol
molecular formula is the actual ratio of elements making up the compound
number of empirical units = molar mass of molecule / empirical mass
empirical units = 168.19 g/mol / 56 g = 3.00
there are 3 empirical units making up the molecular formula
molecular formula = 3 x C₃H₄O
molecular formula = C₉H₁₂O₃
The compound sodium carbonate is a strong electrolyte because it completely dissociates when placed in water into its component ions. The equation of the reaction can be expressed as:

The dissociation leads to the formation of sodium and carbonate ions with the latter held together by its internal covalent bond.
This is unlike weak electrolytes that do not dissociate completely in water or aqueous solutions. Only a small fraction of the solute exists as ions in the solution.
More on strong and weak electrolytes can be found here: brainly.com/question/3410548
Diamond and graphite are made of carbon. So is most of charcoal.
In order to compute mean, you have to add all values of the data set up and divide by the number of data values there are.
In this case, the total sum of all data values is: 81+88+69+65+87=390
The number of data values is 5
To compute mean: 390/5=78
The mean height of the corn stalks is 78cm (C)