Ch. 3: MSM.
1 compound
2 elements sometimes combine to form more than?
1. All matter is composed of extremely small particles called atoms. 2. Atoms of a given element are identical in size, mass, and other properties; atoms of different elements differ in size, mass, and other properties. 3. Atoms cannot be subdivided, created, or destroyed. 4. Atoms of different elements combine in simple whole-number ratios to form chemical compounds. 5. In chemical reactions, atoms are combined, separated, or rearranged.
5 statements of Dalton's theory?
Truuuuuuuuu
A compound is composed of 2 or more different elements. true or false?
Neutron
A nuclear particle that has no electrical charge is called a?
Proton
A positively charged particle found in the nucleus is called a?
Indivisible
Atom was based on the Greek word meaning?
False
Atoms are made up of tiny particles called molecules. true or false?
Truuuuuuu
Atoms are the smallest particles of matter. true or false?
Truuuuuu
Atoms contain protons. true of false?
Electrons
Cathode rays are composed of particles that are now known as?
Protons: charge is +1 and mass is 1. Neutrons: charge is 0 and mass is 1. Electrons: charge is -1 and mass is 0.
Charge and mass of protons, neutrons, and electrons?
+1
Charge of a proton?
-1
Charge of an electron?
0
Charge of the neutron?
moving rapidly outside the nucleus.
Electrons can be found where?
Truuuuuuuuuu
Every atom of copper is identical to every other atom of copper. True or false?
protons and neutrons
Expect for in the simpliest type of hydrogen atom, all nuclei consist of?
Negatively charged.
Experiments with cathode rays being deflected by a magnetic field show that cathode rays are composed of particles that are?
Law of Multiple Proportions
If two or more different compounds are composed of the same 2 elements , then the ratio of the masses of the 2nd element combined with a certain mass of the first element is always a ratio of small whole numbers. What law is that?
An atom consists of a nucleus and a cloud of electrons.
In 1808, John Dalton established his atomic theory. Which of the following is NOT part of Dalton's atomic theory?
A tiny region of positive charge.
In 1911, Ernest Rutherford conducted his now famous goldfoil experiment. During the experiment, alpha particles bombarded a thin piece of gold foil. The alpha particles were expected to pass easily through the gold foil. Every now and then, however, an alpha particle bounced back ---- an unexpected result. Rutherford concluded that these particles were striking?
Neutral
Is an atom positively charged, negatively charged, or neutral?
Mass numbers
Isotopes are atoms of the same element that have different?
Cannot be broken down further.
John Dalton thought that atoms?
The total number of protons and neutrons in an atom of an element.
Mass number is?
Empty
Most of an atom is?
A nucleus
Rutherford called the region that deflected alpha particles?
Gold Foil
Rutherford used what experiment?
1. All elements are composed of tiny indivisible particles called atoms that cannot be broken down further. 2. Atoms of a given element are all similiar in their physical and chemical properties.
State 2 principles from Dalton's atomic theory that have been revised as new information has become available.
All matter is composed of atoms and atoms of any one element differ in properties from of another element remain unchanged.
The 2 important conceptsof our modern atomic theory?
The number of protons in each atom of the element.
The atomic number of an element is?
Law of Definite Proportions
The fact that a chemical compound contains the same elements in exactly the same proportions by mass regardless of the size of the sample or source of the compound is known as what law?
235.
The isotope uranium-235 has 92 protons and 143 neutrons. Therefore, its mass number is?
Truuuuuuu
The mass of an iron atom is different than a silver atom. true or false?
Atom
The smallest unit of an element that can exist either alone or in molecules containing the same or different elements is the?
Electron
The subatomic particle that is least massive is the?
Very small compared with the resst of the atom.
The total volume of the nucleus of an atom is?
Chemical Reaction
The transformation of a substance or substances into one or more new substances is known as a?
Law of Conservation of Mass
This law states that mass is niether created nor destroyed during ordinary chemical reactions or physical changes.
Neutral
What is charge of a neutron?
Thomson
What scientist used cathode-ray tubes in his quest to understand the structure of an atom?
Nucleus
Where are protons found in the atom?
Electron cloud
Where are the electrons found in the atom?
Nucleus
Where are the neutrons found in the atom?
All atoms of a particular element are identical to atoms of other elements.
Which is one way that Dalton's atomic theory has been shown to be incorrect?
Democritus
Who called nature's basic particle an atom?
Thomson
Who created the cathode ray tube?
Thomson
Who found the charge of an electron?
Thomson
Who found the electron?
Rutherford
Who found the nucleus?
Rutherford
Who had the gold foil experiment?
Thomson
Who had the plum pudding model?