Question

If an atom has 43 electrons, 56 neutrons, and 43 protons, what is its approximate atomic mass? What is the name of this clemenc?

Short answer

The element is Technetium, with an atomic mass of 99.

Step-by-step solution

Identify the Atomic Components

First, identify the components of the atom given in the problem: it has 43 electrons, 56 neutrons, and 43 protons. The number of protons is crucial for determining the element, as it corresponds to the atomic number.

Determine the Element

The atomic number is defined by the number of protons in an atom. Since the atom has 43 protons, it corresponds to the element with atomic number 43 on the periodic table. This element is Technetium (Tc).

Calculate the Atomic Mass

The atomic mass of an atom can be approximated by adding the number of protons and the number of neutrons, since electrons have negligible mass. Thus, for this atom, the atomic mass can be calculated as follows: \[\text{Atomic Mass} = \text{Number of Protons} + \text{Number of Neutrons} = 43 + 56 = 99\]

Conclusion

Based on the calculations and identification, the element in question is Technetium, and its approximate atomic mass is 99.

Key concepts

Atomic Number

The atomic number of an element is a fundamental property that defines what type of element an atom is. Each element in the periodic table has a unique atomic number, which is actually the number of protons in the nucleus of an atom. For example, if an atom has 43 protons, its atomic number is 43. This number directly correlates to the specific element on the periodic table, providing a means to identify it.

The atomic number serves as a simple yet powerful organizing principle for the periodic table. Because it describes the number of protons, the atomic number also indirectly tells us about the chemical properties of the element. This is because elements are arranged in the periodic table according to their atomic numbers, which means they are ordered by the increasing number of protons and, in effect, by their electron configurations, which determine chemical behavior.

• The atomic number is specific to each element.
• It determines the element's position on the periodic table.
• It is used to identify elements uniquely and plays a crucial role in chemical reactions.

Atomic Mass

Atomic mass is the total mass of an atom, typically expressed in atomic mass units (amu). It is approximately equivalent to the number of protons and neutrons in the atom, as the electrons have a very tiny mass in comparison to the protons and neutrons and thus can often be neglected in basic calculations.

To find the atomic mass of an element, you sum the number of protons and neutrons in the nucleus. For example, an atom with 43 protons and 56 neutrons will have an atomic mass of approximately 99 amu, as calculated by: \[\text{Atomic Mass} = \text{Number of Protons} + \text{Number of Neutrons} = 43 + 56 = 99\]

This number gives us an idea of how heavy the nucleus of the atom is. It's important to note that while electrons contribute very little to the total mass, their presence and arrangements significantly influence other properties such as the atom's volume and chemical interactions.

• Atomic mass is approximately the sum of protons and neutrons.
• Calculated in atomic mass units (amu).
• Provides insight into the overall mass and stability of the atom.

Elements of the Periodic Table

The periodic table is a systematic arrangement of the chemical elements, organized on the basis of increasing atomic number, which aligns them in rows called periods and columns known as groups.

Each element is represented by a unique symbol and is identified by its atomic number. The table itself serves as a powerful tool to understand the properties of elements, predict their reactions, and comprehend the complex interplay between various atomic features.

• The elements in the same group (column) have similar chemical properties due to having the same number of valence electrons.
• The period number provides information on the number of electron shells. For example, elements in the second period have two electron shells.
• The periodic table can help predict common compounds and reactions based on the elements' positions and relationships.

Understanding the structure of the periodic table enables students and chemists alike to predict the behavior of elements and their compounds. Whether calculating atomic masses or identifying elemental properties based on atomic numbers, the periodic table provides a wealth of information at a glance.