Calculating the Number of Atoms in a Sample of Silicon

Oct 13, 2025 by wbrum.org 47 views

Introduction

Silicon (Si) is a chemical element with the atomic number 14 and the atomic mass of 28.09 g/mol. It is a metalloid that is widely used in various applications, including electronics, construction, and solar panels. In this article, we will discuss the molar mass of silicon and how to calculate the number of atoms in a given sample of silicon.

The Molar Mass of Silicon

The molar mass of silicon is defined as the mass of one mole of silicon atoms. It is a fundamental constant in chemistry that is used to calculate the number of atoms in a given sample of a substance. The molar mass of silicon is 28.09 g/mol, which means that one mole of silicon atoms has a mass of 28.09 grams.

Calculating the Number of Atoms in a Sample of Silicon

To calculate the number of atoms in a sample of silicon, we need to know the mass of the sample and the molar mass of silicon. The mass of the sample is given as 92.8 mg, which is equivalent to 0.0928 grams. We can use the following formula to calculate the number of atoms:

Number of atoms = (mass of sample / molar mass of silicon) x Avogadro's number

Avogadro's number is a fundamental constant in chemistry that is equal to 6.022 x 10^23 atoms/mol. We can plug in the values and calculate the number of atoms as follows:

Number of atoms = (0.0928 g / 28.09 g/mol) x 6.022 x 10^23 atoms/mol

Solving the Equation

To solve the equation, we need to perform the following operations:

Divide 0.0928 g by 28.09 g/mol to get the number of moles of silicon in the sample.
Multiply the result by Avogadro's number to get the number of atoms in the sample.

Let's perform the calculations:

0.0928 g / 28.09 g/mol = 3.30 x 10^-3 mol
3.30 x 10^-3 mol x 6.022 x 10^23 atoms/mol = 1.99 x 10^21 atoms

Conclusion

In conclusion, we have calculated the number of atoms in a 92.8 mg sample of silicon using the molar mass of silicon and Avogadro's number. The result is 1.99 x 10^21 atoms, which is a very large number. This calculation demonstrates the power of chemistry in understanding the properties of materials and the behavior of atoms and molecules.

Applications of Silicon in Chemistry

Silicon is a versatile element that is used in various applications in chemistry. Some of the applications of silicon include:

Semiconductors: Silicon is used to make semiconductors, which are used in electronic devices such as computers, smartphones, and televisions.
Solar Panels: Silicon is used to make solar panels, which convert sunlight into electricity.
Construction: Silicon is used in construction materials such as concrete and cement.
Biotechnology: Silicon is used in biotechnology applications such as DNA sequencing and gene expression.

Conclusion

Q&A: The Molar Mass of Silicon

Q: What is the molar mass of silicon?

A: The molar mass of silicon is 28.09 g/mol.

Q: How is the molar mass of silicon calculated?

A: The molar mass of silicon is calculated by adding up the atomic masses of its constituent atoms. Silicon has an atomic number of 14, which means it has 14 protons and 14 electrons. The atomic mass of silicon is approximately 28.09 g/mol.

Q: What is the significance of the molar mass of silicon?

A: The molar mass of silicon is a fundamental constant in chemistry that is used to calculate the number of atoms in a given sample of silicon. It is also used to calculate the mass of a sample of silicon in terms of its number of moles.

Q: How is the number of atoms in a sample of silicon calculated?

A: The number of atoms in a sample of silicon is calculated using the following formula:

Number of atoms = (mass of sample / molar mass of silicon) x Avogadro's number

Q: What is Avogadro's number?

A: Avogadro's number is a fundamental constant in chemistry that is equal to 6.022 x 10^23 atoms/mol. It is used to convert the number of moles of a substance into the number of atoms.

Q: How is the number of moles of silicon in a sample calculated?

A: The number of moles of silicon in a sample is calculated by dividing the mass of the sample by the molar mass of silicon.

Q: What is the relationship between the number of moles and the number of atoms in a sample of silicon?

A: The number of moles and the number of atoms in a sample of silicon are related by Avogadro's number. The number of moles is equal to the number of atoms divided by Avogadro's number.

Q: What are some of the applications of silicon in chemistry?

A: Silicon is used in various applications in chemistry, including:

Semiconductors: Silicon is used to make semiconductors, which are used in electronic devices such as computers, smartphones, and televisions.
Solar Panels: Silicon is used to make solar panels, which convert sunlight into electricity.
Construction: Silicon is used in construction materials such as concrete and cement.
Biotechnology: Silicon is used in biotechnology applications such as DNA sequencing and gene expression.

Q: What are some of the limitations of silicon in chemistry?

A: Silicon has some limitations in chemistry, including:

Reactivity: Silicon is a relatively reactive element, which can make it difficult to work with.
Cost: Silicon can be expensive to produce, which can limit its use in certain applications.
Availability: Silicon is not as widely available as some other elements, which can limit its use in certain applications.

Conclusion

In conclusion, the molar mass of silicon is a fundamental constant in chemistry that is used to calculate the number of atoms in a given sample of silicon. We have answered some common questions about the molar mass of silicon and its applications in chemistry.