how many molecules of butane are contained in 25.0 ml of butane? the density of butane is 0.6011 g/ml and the molar mass is 58.12 g/mol.

To determine the molecules of butane we can either use multiple steps or use a combined equation based on the following formulas:

Molecules of butane = Moles × Avogadro's Number

Moles of Butane = Mass ÷ Molar Mass

Mass of Butane = volume × Density

∴ Molecules of butane

   = [(volume × Density) ÷ Molar Mass]  × Avogadro's Number

   = ([(25.0 ml × 0.6011 g/ml) ÷ 58.12 g/mol] × (6.022 × 10²³ molecules/mol))

   = 1.557 × 10²³ molecules

a saline water is fed to a reverse osmosis unit at flow rate o rotameter connected to reject (retentate) line reads 8 installed in reject and permeate line reads 15.2 milli siemens/cm and 300 micro siemens/com respectively.

answer : one can design an experiment using a liquid and an additive that can be added to the liquid and observe the chemical changes in the reaction species.

one would need a beaker which is filled with a known amount of the liquid in which thermometer is placed to measure the temperature changes; after addition of the additive to the liquid solution one can note down the temperature change and find whether the reaction is endothermic or exothermic in nature. by subtracting the initial temperature value with the final temperature one can find the temperature changes.

various combinations of liquid and additive can be used. liquid in this case can be a known quantity of water and additives can be epsom salt or without epsom salt the experiment can be conducted to notice the changes. water and ice, hydrogen peroxide and dry yeast, vinegar and baking soda,etc.