Worksheet: Elements, Atoms, and Molecules
In this worksheet, we will practice defining elements, atoms, and molecules and using these terms in the context of materials and physical processes.
What is the difference between a sulfur atom and a sulfur molecule?
- ASulfur atoms can be divided into smaller units, while sulfur molecules cannot.
- BSulfur atoms consist of multiple sulfur molecules bonded together.
- CA sulfur molecule consists of multiple sulfur atoms bonded together.
- DSulfur atoms are reactive, while sulfur molecules are not.
Which of the following best describes a molecule?
- AA single atom of an element
- BA mixture of different elements
- CAtoms of two or more elements bonded together
- DAtoms chemically bonded together in a discrete unit
Which of the following best describes an element?
- AA substance made from more than one type of atom
- BA pure substance
- CAny of the fragments that make up a molecule
- DThe name shared by atoms containing the same number of protons
Which of the following is true of an element?
- AYou can divide up an element into infinitely many pieces.
- BElements are made of at least two types of atom, bonded together.
- CAll the atoms of an element have the same number of protons in their nuclei.
- DElements in the periodic table are arranged in order of increasing mass.
- EAll elements are found in nature in their pure states.
Which of the following is true for molecules?
- AOnce you make a molecule out of atoms, you cannot get the constituent atoms back.
- BMolecules have crystalline structures.
- CMolecules are distinct, covalently bonded collections of atoms.
- DAll molecules are composed of more than one type of atom.
- EAll molecules are made of multiple atoms, all of the same type.
What is the symbol for an atom of the element chlorine?
What state symbol is used to represent a gas in a chemical equation?
What state symbol is used to represent a solid in a chemical equation?
What is the total number of atoms in the following molecule?
Thionyl chloride is a gas with the chemical formula . Which diagram could represent pure ?
What state symbol is used to represent a liquid in a chemical equation?
Carbon can be burned in excess oxygen to form carbon dioxide according to the following equation.
How many different elements, atoms, and molecules are present in this equation?
- AElements: 2, atoms: 3, molecules: 2
- BElements: 2, atoms: 6, molecules: 2
- CElements: 3, atoms: 2, molecules: 6
- DElements: 3, atoms: 2, molecules: 3
- EElements: 6, atoms: 3, molecules: 3
The diagram shows a small number of carbon dioxide and water molecules, with blue circles representing an atom of oxygen. How many atoms of carbon, hydrogen, and oxygen are present in the diagram?
- A10 carbons atoms, 3 hydrogen atoms, and 8 oxygen atoms
- B10 carbons atoms, 8 hydrogen atoms, and 3 oxygen atoms
- C8 carbons atoms, 3 hydrogen atoms, and 10 oxygen atoms
- D3 carbons atoms, 10 hydrogen atoms, and 8 oxygen atoms
- E3 carbons atoms, 8 hydrogen atoms, and 10 oxygen atoms
The energy required to turn liquid chlorine into gaseous chlorine is kJ/mol. The energy required to split a molecule of chlorine into two chlorine atoms is kJ/mol. Which of the following statements explains the difference between these two values?
- AThere are more chlorine atoms than there are chlorine molecules.
- BThe bonds connecting the chlorine atoms are covalent bonds.
- CStronger forces exist between chlorine molecules than the bonds connecting the chlorine atoms in each molecule.
- DThe bonds connecting the chlorine atoms are much stronger than the forces that exist between chlorine molecules.
- EChlorine is already a gas at room temperature and pressure.
Which statement correctly classifies the chemicals in the following equation as either a solid, a liquid, or a gas?
- ASolid: , liquid: , , gas:
- BSolid: , liquid: , , , gas:
- CSolid: , liquid: , gas: , ,
- DSolid: , liquid: , gas:
- ESolid: , liquid: none, gas:
Oxyacetylene torches produce temperatures in excess of . Under these conditions, acetylene burns completely according to the following equation:
What state symbol can be applied to all the components of this reaction under these conditions?
Which of the following statements about elements is false?
- AThe atoms in the element are covalently bonded.
- BElements are made of only one type of atom.
- CElements cannot be broken into simpler forms.
- DElements are pure substances.
- EThe atomic mass of the element is the average mass of the protons and neutrons.
What is the chemical symbol for elemental sodium?