Chemical Elements
What does the chemical element number mean?
How many protons are in the atom
What is an ionic bond?
When one atom 'steals' or takes electrons from another atom in a chemical bond
True or False: The rows are called groups and the columns are called periods
FALSE: Rows are periods and columns are called groups
TRUE OR FALSE: Is popping popcorn a chemical reaction?
No! It is a physical reaction as the kernel is the only thing changing shape
True or False: A chemical reaction can occur if the equation of reactants and products are not balanced
What side of the periodic table are the metals?
Left Side
What is an isotope?
When there is a different number of neutrons in an atom (more or less than protons)
What is a chemical compound?
When there are two or more different elements in a substance
What reaction is the opposite of photosynthesis?
True or False: Neutrons were discovered after electrons
True! Electrons were discovered in 1897 and Neutrons were discovered in 1910!
Name 3 Noble Gases
Helium, Neon, Argon, Krypton, Xenon, Radon
What is a mass number?
Sum of Protons and neutrons
Name 2 characteristics of metallic elements
Shine, Flexible, Conduct heat and electricity, form cations (lose electrons) Solid in normal conditions, high melting and boiling points
rotting, digestion, fireworks, rusting, photosynthesis, respiration, cooking an egg etc
What do you call the substances on each side of a chemical reaction?
Reactants and products
Which common element can form 4 bonds
Carbon
Who had the earliest theory of matter? What was it
Empedocles, Greek philosopher who said all matter was composed of 4 elements: water, air, fire, earth and these affected the properties of the matter
C6H12O6 is commonly known as _______
Glucose
What are 3 signs of a chemical change
heat, light, sound, gas, color change, if it cannot easily go back to its original form
What controls the rate of a reaction?
Temperature and Concentration
How many chemical elements are there (around)
118, but only 114 have been confirmed to exist
What is Dalton's Atomic Theory (need AT LEAST 4 aspects)
All Matter is composed of atoms
Atoms in the same element are identical
Atoms cannot be subdivided, created or destroyed
Atoms of different elements can combine to form different compounds
In Chemical Reactions, atoms are combined, separated, or rearranged
How are chemical elements generally named?
After the person who discovered it, the place it was discovered, or astronomical bodies
What is the law of definite proportions?
any given chemical compound always contains the same elements in the exact same proportions by mass
(Law of conservation of mass)
What are 2 examples of pollution by the chemical industry
Atmospheric Pollution, Pollution of inland waters, soil pollution