The fuel used in many disposable lighters is liquid butane, c4h10. how many carbon atoms are in 1.50 g of butane?

First convert 1.50 grams of butane to moles by dividing it with its molar weight which is 58 g. After getting the number of moles of butane, multiply the amount of moles to four since butane has four carbons. Thus the answer would be 0.026 moles. 

1.5 g of butane contains 6.21 x10^22 atoms of carbon.

Butane is an alkane that contains 4 moles of carbon atoms and 10 moles of hydrogen atom.

     g/mol = g /mole

M = m/n; where M is the molar mass, m is the mass and n is the number of moles

That is; Mass = moles x molar mass

We have; n = m/M

Number of moles = Mass of the substance/ Molar mass

Therefore;

1 mole of particles = molar mass = 6.02 x 10^23 particles

Step 1: moles of butane in 1.5 g of butane

Molar mass of butane is 58.1 g/mol

Therefore;

Moles of butane = mass in g/molar mass

                           = 1.50 g/58.1 g/mol

                           = 0.0258 moles

1 mole of butane contains 4 moles of carbon atoms.

Therefore; 0.0258 moles of butane will contain:

=  0.0258 moles x 4

= 0.1032 moles

Therefore, 1.5 g of butane contains 0.1032 moles of carbon atoms

Using Avogadro's constant;

1 mole of carbon atoms = 6.022 x 10^23 atoms

Therefore;

0.1032 moles of carbon atoms will contain;

= 0.1032 moles x 6.022 x 10^23 atoms

= 6.21 x 10^22 atoms

Keywords: Molar mass, moles, Avogadro's constant

Level: High school

Subject: Chemistry

Topic: Moles

Sub-topic: Avogadros' law