Question

The fuel used in many disposable lighters is liquid butane, C4H10. How many carbon atoms are in 1.50 g of butane?

Answer 1

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.

Further Explanation:

Moles, Atomic mass and Molar mass  

• 1 mole of a pure substance contains a mass that is equal to the relative atomic mass or molecular mass of the substance.
• Therefore; molar mass is given as grams per mole of a substance
• Molar mass of any element is equal to the atomic mass of that element in the unit of grams.
• Hence;
• Molar mass = mass of a substance/ Number of moles

     g/mol = g /mole

• Thus:

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

• From this relationship we can therefore, calculate mass by multiplying the number of moles by molar mass of a substance.

That is; Mass = moles x molar mass

• To calculate number of moles;

We have; n = m/M

Number of moles = Mass of the substance/ Molar mass

• Molar mass is also equal to the mass of  6.02*10^23 particles of an element. 

Therefore;

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

In this case;

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

Step 2: Moles of Carbon in 1.5 g of butane

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

Step 3: Number of atoms in 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

Learn more about:

• Relative atomic mass: brainly.com/question/4079113
• Moles calculation: brainly.com/question/4079113
• Molar mass: brainly.com/question/4079113

Level: High school

Subject: Chemistry

Topic: Moles

Sub-topic: Avogadros' law

Answer 2

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.