Atomic Structure and Chemistry Basics

What is the purpose of the oxidation number in transition metals?

To calculate the mass number of an atom
To indicate the charge of an ion in an ionic compound
To determine the number of protons in an atom
To show the different possible charges of the metal (correct)

What is the formula to calculate the number of neutrons in an atom?

Number of electrons - Number of protons
Mass number (A) - Atomic number (Z) (correct)
Atomic number (Z) - Number of protons
Number of protons + Number of electrons

How do you calculate the number of electrons in an ion?

By adding the protons and neutrons
By subtracting the atomic number from the mass number
By subtracting the charge from the atomic number (correct)
By subtracting the charge from the mass number

What is the difference between the molecular formula and the empirical formula?

The molecular formula shows the actual number of atoms, while the empirical formula shows the simplest ratio of atoms (B) Signup and view all the answers

Which of the following is a characteristic of isotopes?

They have the same atomic number but different mass number (C) Signup and view all the answers

What is the suffix used to form the name of an anion?

-ide (D) Signup and view all the answers

What is a cation?

A neutral atom that loses electrons (B) Signup and view all the answers

What is the purpose of the subscript in a chemical formula?

To indicate the number of atoms of an element (B) Signup and view all the answers

What is the rule regarding the quantum numbers of electrons in an atom?

No two electrons in an atom can have the same set of four quantum numbers n, l, ml, and ms. (B) Signup and view all the answers

What is the representation of a compound that shows the order and arrangement of specific atoms?

Structural formula (B) Signup and view all the answers

What is the term for the electrostatic forces holding the ions together?

Ionic bonds (D) Signup and view all the answers

What is the formula to calculate the mass number of an atom?

Number of protons + Number of neutrons (D) Signup and view all the answers

How do electrons fill energy levels in an atom?

Electrons fill the lowest available energy levels before filling higher levels. (B) Signup and view all the answers

What is the correct order for filling sublevels other than s?

Electrons are placed in individual orbitals before they are paired up with parallel spin. (C) Signup and view all the answers

What type of substance is characterized by having at least one unpaired spin electron?

Paramagnetic (B) Signup and view all the answers

How are elements arranged in the periodic table?

Increasing atomic number (D) Signup and view all the answers

What do elements in the same group have in common?

The same arrangement of electrons at the outer shell of their atoms (D) Signup and view all the answers

What is a characteristic of a chemical reaction?

Change in chemical composition (C) Signup and view all the answers

What is the purpose of the arrow in a chemical equation?

To indicate the direction of the reaction (D) Signup and view all the answers

What is the correct notation for a gas in a chemical equation?

(g) (D) Signup and view all the answers

What is the correct step in balancing a chemical equation?

Balance other elements and then H and O (C) Signup and view all the answers

What is a characteristic of acids?

They have a sour taste (A) Signup and view all the answers

What is the purpose of subscripts in a chemical formula?

To indicate the number of atoms in a molecule (A) Signup and view all the answers

What is the mole fraction of methane in the given sample of natural gas?

0.94 (A) Signup and view all the answers

What is the unit of molarity?

moles/liter (B) Signup and view all the answers

What is the role of hydration in a solution?

To stabilize ions in solution (A) Signup and view all the answers

What is the molality of a solution containing 0.249 moles of sulfuric acid in 198 g of water?

1.26 m (C) Signup and view all the answers

What is the purpose of square brackets [ ] in a chemical equation?

To indicate the concentration of the solution (C) Signup and view all the answers

How many grams of sodium sulfate are needed to prepare a 1 molal solution?

142 g (C) Signup and view all the answers