Science test chemistry part 2 Flashcards
What is the difference between a group and a period?
-Group: vertical on the periodic table, elements with similar chemical properties
-Period: horizontal on the periodic table, same amount of electron shells, elements with different chemical properties
What are valence electrons?
The number of valence electrons is equal to the atom’s main group number
Properties of alkali metals are…
high thermal and electrical conductivity, lustre, ductility, and malleability
Properties of Alkaline Earth metals are…
low densities, melting points and boiling points,
Properties of Halogens are…
low melting and boiling points, and are sparingly soluble in water
Properties of Noble gases are…
colorless, odorless, tasteless, and non-flammable under standard conditions
Why are alkali metals more reactive than alkaline earth metals?
alkali metals have just one valence electron and this makes atoms more reactive
What is the difference between metals, non-metals, and metalloid in terms of properties?
metals are good at conducting energy, non-metals aren’t, and metalloids in the middle of that, not as good as conducting as metal but better than non-metal
How do you know which is the atomic mass and which is the atomic number?
The atomic number is in the left top corner of an element, and the atomic mass in the bottom of element, sometimes with decimals.
What did democritus do?
developer of atomic theory of the universe
What did dalton do?
introducing the atomic theory into chemistry
What did Tompson do?
discovered the electron
What did Rutherford do?
discovered alpha and beta rays
What did Chadwick do?
discovered the neutron
What did Bohr do?
made the model of an atom
which has smallest mass? proton, neutron, electron?
electron
which is uncharged? proton, neutron, electron?
neutron
which is found outside the nucleus? proton, neutron, electron?
electrons
which two have almost the same mass? proton, neutron, electron?
protons and neutrons
what is an isotope?
Atoms with the same number of protons but different numbers of neutrons
what is an ion?
an atom or group of atoms that has an electric charge
what is an element?
a substance that cannot be broken down into any other substance
what is the difference between cation and anion?
Anion- negatively charged, non-metals
Cation- positively charged, metals
which elements form ionic compounds?
elements that are metals and elements that are nonmetals
[example: calcium (Ca) and Chlorine (Cl)]
which elements form molecular compounds?
two or more nonmetal atoms [example: Hydrogen (H) and oxygen (O)]
which elements are metals? which are non-metals?
Metals: Lithium, Beryllium, Sodium, magnesium, Aluminum, Potassium, and calcium
Non-Metals: Hydrogen, Helium, Carbon, Nitrogen, Oxygen, Fluorine, Neon, Phosphorous, Sulphur, Chlorine, and Argon
what is an atom?
The smallest part of a substance that cannot be broken down chemically
which elements are metalloids?
boron, silicon
What are the properties of metals, nonmetals, and metalloids?
Metals: Most metals have a shiny metallic luster and reflective surface. Nonmetals: Nonmetals are generally dull or nonreflective and do not have a metallic luster. Metalloids: Metalloids can have a metallic or nonmetallic appearance, depending on the element
What are the names of Groups1, 2, 17 ,and18
Group 1: The Alkali Metals.
Group 2: The Alkaline Earth Metals.
Group 17: The Halogens.
Group 18: The Noble Gases.
What are the different models of atoms?
Billiard Ballmodel, Plum Pudding model, Planetary model, Bohr-Rutherford model
How does an isotope differ from a neutral atom?
Neutral atoms have the same number of electrons and protons. Atoms of an element that contain different numbers of neutrons are called isotopes.
How many valence electrons are there in Groups1,2,13,14,15,16,17,18?
Group 1: 1
Group 2: 2
Group 13: 3
Group 14: 4
Group 18: 8
What is the difference between an ionic and covalent bond?
Covalent bonds share electrons and ionic bonds donate electrons
How do you name ionic compounds?
with the cation first and the anion last
