Atoms and Elements
What is an atom?
An atom is the smallest unit of matter that retains the properties of an element.
What are the three common states of matter?
The three common states of matter are solid, liquid, and gas.
What is a chemical reaction?
A chemical reaction is a process where substances change into new substances.
What is a mixture?
A mixture is a combination of two or more substances that are not chemically combined.
What does the periodic table show?
The periodic table shows all known elements arranged by increasing atomic number.
What are the three main particles in an atom?
The three main particles in an atom are protons, neutrons, and electrons.
What state of matter has a fixed shape and volume?
A solid has a fixed shape and volume.
What is produced in a chemical reaction?
New substances called products are produced in a chemical reaction.
What is a compound?
A compound is a substance made from two or more elements chemically bonded together.
What is the symbol for hydrogen?
The symbol for hydrogen is H.
What is an element?
An element is a pure substance made up of only one kind of atom.
Which state of matter takes the shape of its container but has a fixed volume?
A liquid takes the shape of its container but has a fixed volume.
What does it mean if a reaction is reversible?
A reversible reaction is one where the products can change back into the original reactants.
Can a mixture be separated easily?
Yes, mixtures can usually be separated by physical methods.
Are elements arranged in order of increasing atomic number or mass?
Elements are arranged in order of increasing atomic number.
Can an element be broken down into simpler substances?
No, an element cannot be broken down into simpler substances by chemical means.
What state of matter has neither fixed shape nor fixed volume?
A gas has neither fixed shape nor fixed volume.
Give one example of a simple chemical reaction.
An example is burning wood (wood + oxygen → ash + smoke).
Are compounds made of one or more elements?
Compounds are made of two or more elements.
Name one metal and one non-metal from the periodic table.
Metal example: Iron (Fe); Non-metal example: Oxygen (O).
Give an example of an element.
Examples include hydrogen (H), oxygen (O), and carbon (C).
Name a substance that is commonly found in the gas state.
Oxygen (O2) is commonly found in the gas state.
What do you call the starting substances in a chemical reaction?
The starting substances are called reactants.
Give an example of a common compound.
Water (H2O) is a common compound.
What color are metals usually shown as in most periodic tables?
Metals are usually shown in silver or gray colors on most periodic tables.