Chemistry Mid Term Review Quiz

What is the balanced chemical equation for the reaction between hydrochloric acid and sodium hydroxide?

• HCl + NaOH → NaCl + H2O

• H2O + NaOH → NaCl + HCl

• H2O + NaCl → HCl + NaOH

• HCl + NaOH → NaOH + HCl

Explain the difference between exothermic and endothermic reactions with examples.

• Exothermic reactions release heat energy, while endothermic reactions absorb heat energy.

• Exothermic reactions release chemical energy, while endothermic reactions release heat energy.

• Exothermic reactions absorb heat energy, while endothermic reactions release heat energy.

• Exothermic reactions release light energy, while endothermic reactions absorb heat energy.

What is the role of a catalyst in a chemical reaction?

• A catalyst increases the rate of the reaction by lowering the activation energy

• A catalyst alters the products of the reaction

• A catalyst decreases the rate of the reaction

• A catalyst changes the reactants of the reaction

What does the atomic number of an element represent and how is it connected to the nucleus?

• The atomic number represents the number of electrons in the nucleus.

• The atomic number represents the number of neutrons in the nucleus.

• The atomic number represents the number of protons in the nucleus.

• The atomic number represents the number of isotopes in the nucleus.

what is the correct ground state nelectron configuration for the element with atomic # 12

• 2-8-8

• 2-8-2

• 2-7-3

• 2-8-8-2

How does atomic radius change as you move across a period in the periodic table?

• Decreases

• Increases

• Fluctuates

• Remains constant

What is the trend in electronegativity as you move down a group in the periodic table?

• Electronegativity decreases

• Electronegativity increases

• Electronegativity remains constant

• Electronegativity becomes unpredictable

What is the significance of the 'octet rule' in chemistry?

• It states that atoms lose, gain or share electrons to have eight electrons in their outer shell.

• It states that all elements have eight protons in their nucleus.

• It states that all chemical reactions involve eight molecules.

• It states that all elements have eight isotopes.

What is the term for the amount of energy required to remove an electron from an atom?

• Ionization energy

• Electron affinity

• Atomic radius

• Electronegativity

What is the term for the number of protons and neutrons in an atom's nucleus?

• Atomic number

• mass number

• Atomic radius

• Atomic volume