One
________ proposed the atomic theory in 1808.
a. Lavoisier
b. Chadwick
c. Dalton
d. JJ Thomson
c. Dalton
he characteristics of atoms according to Democritus are __________.
a. Unchangeable
b. Indestructible
c. Always existed
d. All of the above
D. All of the above
The Law of Conservation of Mass states that the mass of the products will be equal to
the mass of the reactants such that the total mass remains the same.
a. TRUE
b. FALSE
a. True
All matter is made of _________.
a. water
b. gasses
c. atoms
d. carbon
c. atoms
The neutron has a charge.
a. TRUE
b. FALSE
b. FALSE
Cathode rays travel in a straight line.
a. TRUE
b. FALSE
a. TRUE
Which of the following statement(s) is/are true for protons?
a. Protons have a positive charge
b. Protons are much larger and heavier than electrons
c. The number of protons for a given atom never changes
d. All of the above
d. All of the above
Which of the following is/are the correct explanation of the plum pudding model?
a. The electrons are the pudding and the protons are scattered like pieces of plum.
b. The protons are the pudding and the electrons are scattered like pieces of plum.
c. The neutrons are the pudding and the electrons are scattered like pieces of plum.
d. The protons are the pudding and the neutrons are scattered like pieces of plum.
b. The protons are the pudding and the electrons are scattered like pieces of plum.
As an electron moves further away from the atom’s nucleus, its energy ______.
a. increases
b. decreases
c. first increases, then decreases
d. fluctuates randomly
a. increases
20. The mass number of an atom is calculated by adding up the number of protons and electrons in that atom.
a. TRUE
b. FALSE
b. FALSE
A student mixed 500.00 g of sugar and 120.00 g of salt in 106.00 g of lime juice. The net
total weight of the mixture is _______.
a. 726. g
b. 726.0 g
c. 726.00 g
d. 726.000 g
C. 726.00 g
The element with 11 protons and 11 neutrons must be _______.
a. nitrogen (N)
b. helium (He)
c. sodium (Na)
d. potassium (K)
c. sodium (Na)
Who performed the gold foil experiment to identify the relative size of the nucleus?
a. Ernest Rutherford
b. John Dalton
c. J.J. Thomson
d. Niels Bohr
a. Ernest Rutherford
A reaction of 15.00 g hydrochloric acid and 7.00 g lithium hydroxide produces 12.50 g
water and _____ g of lithium chloride.
a. 9.5
b. 9.50
c. 9.500
d. 4.50
b. 9.50
In the compound CH₄, find the carbon to hydrogen mass ratio.
a. 2:3
b. 3:1
c. 6:1
d. 1:3
b. 3:1
The element _______ was used as the basis to calculate the atomic mass of all other
elements.
a. carbon
b. oxygen
c. fluorine
d. hydrogen
a. carbon
The atom chlorine-37 has ____ neutrons.
a. 37
b. 18
c. 20
d. 35
c. 20
Which of the following statements is true about the atoms of any given element??
a. They have the same number of protons as the number of neutrons.
b. They have the same size as the atoms of all other elements.
c. All atoms of a given element are identical in that they have the same number of
protons.
d. All atoms of a given element are not identical in that they have a different number
of protons.
c. All atoms of a given element are identical in that they have the same number of
protons.
Isotopes of the same element differ in their ________.
a. mass numbers
b. number of neutrons
c. atomic numbers
d. Both A and B
d. Both A and B
A given chemical compound always contains the same elements in the exact same
proportions by mass is the Law of ________________________.
a. Multiple Proportions
b. Definite Proportions
c. Conservation of Mass
d. Conservation of Chemical Composition
b. Definite Proportions
Water is 11.2 % hydrogen in water. The percentage of oxygen present in water is ____.
a. 88.80 %
b. 88.8 %
c. 89.0 %
d. 50.0 %
b. 88.8 %
Select all possible answers: Which statement(s) is/ are FALSE?
a. Neutral atoms are made of specific numbers of protons and electrons but the
number of neutrons they possess can vary a little bit.
b. The number of protons identifies the element.
c. Protons and neutrons repel each other and position themselves far apart inside the atom.
d. Atoms of all elements are about the same size.
c. Protons and neutrons repel each other and position themselves far apart inside the atom.
d. Atoms of all elements are about the same size.
25. The atomic mass of isotope copper-___ (for Cu) is 64.534 amu.
a. 63
b. 64
c. 65
d. 29
c. 65
The discrete amounts of energy that are absorbed or released by an atom when an
electron changes energy levels are called ________.
a. quarks
b. quanta
c. orbitals
d. fermions
b. quanta
Select all possible answers. Which of the following are features of the nucleus of an
atom?
c. The nucleus contains electrons and neutrons.
d. The nucleus has a tiny size relative to the total space of the atom.
e. It has a relatively great mass compared to the other components of the atom.
f. The nucleus contains protons and neutrons.
g. The nucleus is located at the center of the atom.
d. The nucleus has a tiny size relative to the total space of the atom.
e. It has a relatively great mass compared to the other components of the atom.
f. The nucleus contains protons and neutrons.
g. The nucleus is located at the center of the atom.