Science - Atomic theory and Chemistry

what is an atom?

• the smallest part of an element that has all of the element's properties

• the smallest Pokemon

• the nickname of Tails the fox

• the smallest robot created by Dr. Robotnik

do iron and copper atoms have same properties?

• yes

• no

Answer explanation

Atoms of copper are not the same as atoms of iron. This is

why a piece of copper metal has different properties than a piece of iron metal. Iron’s strength is useful to artists because it can be used to support heavy weights. Copper has an attractive colour and lustre, and its malleability makes it easy to work with.

what does atom mean in Greek?

• indivisible

• can be divided

• as fast as Sonic

Answer explanation

We get the modern term “atom” from the Greek atomos, meaning indivisible.

what is Atomic theory?

• the study of the nature of atoms and how they combine to form all types of matter

• the study of Sonic's speed

• the study of the smallest of Dr. Robotnik's robot

Answer explanation

Atomic theory is the study of the nature of atoms and how they combine to form all types of matter. Atomic theory helps us to understand why there are different kinds of atoms. It explains how atoms combine to form over 100 known elements and all other forms of matter, including compounds and mixtures.

what is Democritus' hypothesis related to the Atomic theory?

• most of the matter is made from combinations of simple forms of matter that could not be broken down any more

• no atom can go faster than Sonic

• all matter is made of smallest Pokémon

Answer explanation

About 440 B.C.E., the Greek philosopher Democritus hypothesized that breaking down rock into powder and then grinding the powder further would reduce it to tiny bits of matter that could not be broken down any more. His idea was not popular and, at the time, there was no experimental evidence to support it.

what was John Dalton's idea about Atomic theory?

• all atoms were like small spheres but they could have different properties (size, mass, or colour)

• all planets of the Solar system go around the Sun

• each type of atom represents a different world in the Pokémon universe

Answer explanation

John Dalton suggested that atoms were like small spheres. Each element, he proposed, had a unique type of atom with a particular mass.

what was J.J. Thomson's idea about Atomic theory?

• atoms are a positive sphere made from a combination of particles, including negatively charged electrons

• atoms grow on trees and can also be found in rivers and lakes

• atoms can get dizzy if you spin them too much

Answer explanation

In 1897, Thomson proposed a revolutionary new model for

atoms, in which each atom was composed of smaller particles. Because Thomson had detected negatively charged particles, he

reasoned that atoms, which have no overall electric charge, must

also contain positive charges. Thomson’s model of the atom is a positive sphere with negative electrons scattered throughout it.

what was Ernest Rutherford's idea about Atomic theory?

• all atoms contain a positively charged, massive nucleus surrounded by negatively charged electrons

• all atoms contain negatively charged nucleus surrounded by positively charged electrons

• all atoms contain electrons in the center surrounded by many nuclei

Answer explanation

Rutherford predicted that all atoms contain nucleus. All of the atom's positive charge and most of the atom's mass were concentrated at a tiny point in the centre. The electrons surrounded the nucleus and occupied most of the atom's volume, but they contained only a small fraction of the atom's total mass.

what was Niels Bohr's idea about Atomic theory?

• electrons surround the nucleus in specific energy levels (shells) and jump between these shells by gaining or losing energy

• nuclei surround electrons and jump on different energy levels

• if an atom spins too fast it will lose all its electrons and the nucleus

Answer explanation

Bohr suggested that electrons surround the nucleus in specific energy levels, called shells. He discovered that electrons jump between these shells by gaining or losing energy. Each shell can contain only a specific number of electrons.

label this Bohr diagram

a

b

c

electron

nucleus

electron shells

Answer explanation