This scientist suggested that matter is made up of tiny, indivisible atoms.[1]
Answer: Who is Dalton
This number equals the number of protons in an atom.[1]
Answer: What is the atomic number?
This number on a periodic table entry tells you how many protons an atom of the element has.[1]
Answer: What is the atomic number
Each horizontal row on the periodic table is called this.[1]
Answer: What is a period?
This colourless, odourless, tasteless gas is highly flammable and can be used to power some automobiles.[1]
Answer: What is hydrogen
He proposed that atoms contain negatively charged particles later called electrons.[1]
Answer: Who is Thomson
This number equals the total number of protons plus neutrons in an atom.[1]
Answer: What is the mass number
The periodic table entry shows this value as a decimal representing the average mass of the element’s atoms.[1]
Answer: What is the average atomic mass
Each vertical column on the periodic table is called a group or this.[1]
Answer: What is a family
Most hydrogen on Earth is found combined with oxygen to form this compound.[1]
Answer: What is water?
This scientist discovered the nucleus and its subatomic particles using a gold foil experiment.[1]
Answer: Who is Rutherford
In a neutral atom, the number of these particles equals the number of protons.[1]
Answer: What are electrons
The one- or two-letter set used to represent an element is called this.[1]
Answer: What is a chemical symbol
Elements in the same vertical column have similar values for these properties.[1]
Answer: What are chemical properties
Oxygen is produced by plants as a by-product of this process that uses sunlight.[1]
Answer: What is photosynthesis
He proposed that electrons are located in shells around the nucleus.[1]
Answer: Who is Bohr
This type of particle imbalance produces the electric charge on an ion.[1]
Answer: What is an imbalance between protons and electrons?
This is the full written name of an element, such as “magnesium” or “oxygen.”[1]
Answer: What is the element name
Group 1 elements (except hydrogen) are known by this family name.[1]
Answer: What are alkali metals
In this process, cells combine oxygen with sugar to release energy.[1]
Answer: What is cellular respiration?
These tiny entities are the basic building blocks of all matter, according to atomic theory.[1]
Answer: What are atoms
Too many electrons on an atom produce this type of charge.[1]
Answer: What is a negative charge
In the magnesium entry “Mg 24.3,” the number 24.3 is this.[1]
Answer: What is the average atomic mass
Group 2 elements are called this family of metals.[1]
Answer: What are alkaline earth metals
Sodium reacts with water to release hydrogen gas, heat, and a toxic compound used in this household product.[1]
Answer: What is drain cleaner