Combustion of hexane can be illustrated by the following reaction:
2C6H14 + 19O2 ...........> 12CO2 + 14H2O
From the periodic table:
mass of hydrogen = 1 gram
mass of oxygen = 16 grams
mass of carbon = 12 grams
Therefore:
molar mass of hexane = 6(12)+14(1) = 86 grams
mass of water = 2(1)+16 = 18 grams
From the balanced equation above:
2(86) = 172 grams of hexane produce 252 grams of water. To know the amount of water produced from 1.33 grams of hexane, all you have to do is cross multiplication as follows:
amount of water = (1.33x252) / 172 = 1.9486 grams
The empirical formula : Na₂Cr₂O₇
<h3>Further explanation</h3>
Given
170 g sample contains :
29.84 g sodium, 67.49 g chromium, and 72.67 g oxygen
Required
The compound's empirical formula
Solution
mol ratio of elements :
Na : 29.84 : 23 g/mol = 1.297
Cr : 67.49 : 51,9961 g/mol = 1.297
O : 72.67 : 16 g/mol = 4.54
Divide by 1.297
Na : Cr : O = 1 : 1 : 3.5 = 2 : 2 : 7
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)
