Chapter 1 - Chemistry Flashcards
(28 cards)
What charge are protons?
Positive
What charge are neutrons?
Neutral
What charge are electrons?
Negative
What charge are atoms?
Neutral
What is an isotope?
An atom with the same number of protons but a different number of neutrons
What are compounds?
Compounds are substances that contain atoms of different elements
What is the meaning of a mixture?
A mixture is made up of two or more substances (elements or compounds) that are not Chemically combined together.
How can mixtures be separated?
Mixtures can be separated through physical means such as filtration, distillation and crystallisation
What is an ion?
An ion is a charged atom (or group of atoms)
What is an element?
A substance made up of atoms that all have the same number of protons in their nucleus
Give two methods that can be used to separate mixtures
Filtration
Crystallisation
What does filtration do?
Filtration separates insoluble solids from liquids
What did scientists used to think about the shape of the atom?
That they were solid spheres
Which scientist changed the nuclear model of the atom?
Niels Bohr
When are atoms stable?
When they have a full outer shell.
How was the periodic table arranged in the early 1800s?
They were arranged by atomic mass.
How did Mandeleev arrange the periodic table?
Arranged them mainly by atomic mass, also left gaps for elements to be discovered.
State two changes that Mandeleev made to the periodic table
Sorted elements mainly by their atomic mass
Left gaps in the table
Where are metals and non-metals found in the periodic table?
Metals are found on the left, non-metals found on the right
What are most elements made out of?
Metals
What can metals form when they react?
Positive ions
What are group 1 metals known as?
Alkali metals
How many electrons do group 1 metals have in their outer shell?
One electron
What do alkali metals form with non-metals?
Ionic compounds
