Understanding Atomic Structure and Charge

The video tutorial covers practice problems related to atoms, isotopes, and ions. It begins with definitions and key concepts, such as mass number, atomic number, and charge. The instructor then guides through solving problems involving nitrogen atoms and ions, explaining how to determine atomic numbers, mass numbers, and electron counts. Additional notes include assumptions about charge and mass rounding using the periodic table.

What is the primary difference between an atom and an ion?

• An atom has a charge, while an ion is neutral.

• An atom is neutral, while an ion has a charge.

• An atom is larger than an ion.

• An atom has more protons than electrons, while an ion has more electrons than protons.

What does the atomic number of an element represent?

• The total mass of the element.

• The total number of electrons in the element.

• The total number of neutrons in the element.

• The total number of protons in the element.

How do you calculate the number of neutrons in an atom?

• Divide the mass number by the atomic number.

• Multiply the atomic number by the mass number.

• Add the atomic number to the mass number.

• Subtract the atomic number from the mass number.

If an atom has 7 protons and a charge of +3, how many electrons does it have?

• 4 electrons

• 3 electrons

• 7 electrons

• 10 electrons

What assumption is made about the charge of an atom if no charge is indicated?

• The charge is assumed to be +1.

• The charge is assumed to be -1.

• The charge is assumed to be +2.

• The charge is assumed to be zero.

In chemistry, what does a negative sign without a number indicate about the charge?

• It indicates a charge of -2.

• It indicates a charge of -1.

• It indicates a charge of zero.

• It indicates a charge of -3.

How should you determine the mass of an element if it is not provided?

• Assume the mass is zero.

• Use the most common mass from the periodic table and round it.

• Use the atomic number as the mass.

• Guess the mass based on similar elements.

What is the rounded mass of manganese (Mn) according to the periodic table?

• 56

• 53

• 55

• 54

If an element's mass is not given, what is the first step to find it?

• Assume it is the same as the atomic number.

• Assume it is zero.

• Use the mass of a similar element.

• Look it up on the periodic table.

Why can't an atom have a mass of zero?

• Because it would have no neutrons.

• Because it would have no protons.

• Because it would have no electrons.

• Because it would not be an atom.