Chapter 1
Hypothesis
What is the most common state of matter in the universe?
Plasma
Substances formed from atoms of two or more different elements are called
Compounds
What would be a useful method for visualizing and describing atoms?
Different structural forms of the same element are called
Allotropes
A variable that does not change as another variable changes
Control
What is the SI unit of pressure?
Pascal
What is it called when you have a heterogeneous mixture that allows the different particles to settle?
Suspension
Two elements with the same number of protons but a different number of neutrons are called
isotopes
A(n) ______ is a molecule composed of 2 atoms of the same element
Diatomic Molecule
The amount of matter in an object
Mass
What is the amount of energy needed to change a solid to a liquid at its melting point
heat of fusion
What is the process that can separate liquids using physical change?
distillation
The horizontal rows on the periodic table are called _____ and the vertical columns on the periodic table are called ______.
periods, groups
What are the least reactive elements?
Noble gases
A test set up under controlled conditions
Experiment
Which of these examples uses Pascal's Principle?
a) Aerodynamics b) buoyancy c) hydraulic lift d) changes in state
A visible sunbeam is an example of which of the following?
The Tyndall Effect
What determines the chemical properties of an element?
Valence electrons
What are the four main elements in the human body?
Hydrogen, Oxygen, Nitrogen, Carbon
The amount of space occupied by an object
Which law states that volume increases with temperature (At constant pressure)
Charle's Law
What does the Law of Conservation of Mass state?
Matter is not created or destroyed in a chemical or physical change
The _____ of an element is the number of _____ of an atom of that element
atomic number, protons in the nucleus
When an atom GAINS an electron, the atom is ___ charged. When an atom LOSES an electron, the atom is ____ charged.
negatively, positively