Classifying matter and atomic theory Flashcards
1
Q
Which of the following scientists discovered that atoms contain negatively charged particles later known as electrons? A. Niels Bohr B. John Dalton C. Ernest Rutherford D. J.J. Thomson
A
D. J.J. Thomson
2
Q
In an atom’s natural state, the number of protons equals the number of... A. Nuclei B. Electrons C. Neutrons D. Isotopes
A
B. Electrons
3
Q
What information in the element square indicates the number of protons in an atom?
A. The position of the elements in a column
B. The element’s chemical symbol
C. The element’s atomic number
D. The element’s atomic mass
A
C. The element’s atomic number
4
Q
Which of the following scientist discover that there must be a center to the atom , nucleus, which contains positive charges? A. Niels Bohr B. John Dalton C. Ernest Rutherford D. JJ Thomson
A
C. Ernest Rutherford
5
Q
Which subatomic particles in atoms move rapidly in the cloud like region around the nucleus? A. Electrons B. Protons C. Neutrons D. Nuclei
A
A. Electrons
6
Q
Pure substances that cannot be broken down chemically or physically into other substances are… A. Elements B. Compounds C. Mixtures D. Solutions
A
A. Elements
7
Q
All elements are composed of extremely small particles called… A. Compounds B. Mixtures C. Atoms D. Molecules
A
C. Atoms
8
Q
Which of these statements are false?
A. Oxygen and gold are examples of elements
B. Elements are pure substances
C. Atoms of different elements combine to form compounds
D. Atoms of different elements are the same
A
D. Atoms of different elements are the same
9
Q
The forces of attraction that holds two or more elements together in a compound are known as… A. Density B. Gravity C. Physical bonds D. Chemical bonds
A
D. Chemical bonds
10
Q
Lemonade consist of several substances that are not chemically combined, so lemonade is classified as a… A. Element B. Compound C. Mixture D. Pure substance
A
C. Mixture
