Final Exam Test Bank

In which sequence were atomic particles discovered?

• neutrons, protons, electrons

• protons, electrons, neutrons

• electrons, protons, neutrons

• protons, neutrons, electrons

In what way do currently accepted models of the atom differ from the model in the drawing?

• Electrons do not have an elliptical orbit.

• The nucleus contains only protons.

• All electrons are the same distance from the nucleus.

• Electrons do not have a negative charge.

What type of elements can react with metals to form salts?

• halogens

• metalloids

• noble gases

• semiconductors

Which of the following statements best explains why potassium (K) reacts easily with bromine (Br)?

• Potassium and bromine both have valence electrons in the fourth energy level.

• Potassium and bromine have the same number of electrons in their highest energy levels.

• Potassium has one electron in its highest energy level, and bromine needs one electron to complete its highest energy level.

• Potassium needs one electron to complete its highest energy level, and bromine has an extra electron in its highest energy level.

What is the most common element in the universe?

• carbon

• hydrogen

• nitrogen

• oxygen

Refer to this portion of the periodic table to answer the question that follows.

Which element in this group would be the least likely to react with other elements?

• Boron

• Carbon

• Neon

• Oxygen

This is an electron dot diagram:

Which element is represented?

• boron (B)

• phosphorus (P)

• sulfur (S)

• bromine (Br)

A change in which one or more substances are converted into new substances is a __________.

• physical change

• nuclear reaction

• chemical change

• chemical fusion

Which is a way to describe a chemical reaction using chemical formulas and symbols?

• synthesis

• a physical law

• the law of conservation of matter

• a chemical equation

What coefficient should be used to make the following equation balanced?

N₂+O_{2 →} _______NO 

• 1

• 2

• 3

• 4