physics ch. 11

mostly empty space themselves

A granite block is mostly empty space because the atoms in the granite are

56 neutrons

A nucleus with an atomic number of 44 and a mass number of 100 must have

d. all of the above

An atomic model of the atom is a. a stepping stone to further understanding. b. a symbolic representation of the atom. c. an abstraction enabling predictions. d. all of the above

protons

An element is distinct because of its number of

has different numbers of neutrons for the same element

An isotope is simply an atom that

protons in the nucleus

Atomic number refers to the number of

scanning electron microscopes and electron beams

Atoms can be photographed by

particles larger than atoms bumping into them

Brownian motion is caused by

smaller

Compared to the average size of a hydrogen atom, the average size of a helium atom is

Mass number is the number of nucleons; atomic mass is the total mass of an atom.

Distinguish between mass number and atomic mass.

It has a different number of neutrons.

How does one isotope differ from another?

The numbers are the about the same

How does the approximate number of atoms in the air in your lungs compare with the number of breaths of air in Earth's atmosphere?

its equal and opposite

How does the electric charge of a proton compare with the electric charge of an electron?

7

How many shells are represented in the presently known periodic table?

nucleons in the nucleus

Mass number refers to the number of

Electrons in one atom repel the electrons in another.

Since atoms are mostly empty space, why don't we fall through a floor we stand on?

C. Both of the above

The atomic number of an element matches the number of A. protons in the nucleus of an atom. B. electrons in a neutral atom. C. Both of the above. D. None of the above.

electrons

The chemical properties of matter are due mostly to their

gold atoms

The element gold contains

orbital electrons

The number of protons in a neutral atom is balanced by an equal number of

Carbon, Hydrogen, Oxygen, Nitrogen, Calcium

What are the five most common elements in the universe?

collisions with invisible particles

What causes dust particles and tiny grains of soot to move with Brownian motion?

random motions

What did Robert Brown see in his microscope?

The # of protons in its nucleus

What does the atomic number of an element tell you about the element?

hydrogen

What element has the lightest atoms?

hydrogen

What is the most abundant element in the known universe?

electric

What kind of attraction pulls electrons close to the atomic nucleus?

In the nucleus as protons

Where in the atom is most of its mass concentrated?

quark

Which is the smallest particle?

c. neutrons

Which of the following are electrically neutral? a. ions b. electrons c. neutrons d. proton

D. Atoms are manufactured in plants, and in humans during pregnancy.

Which of the following are incorrect statements about the atom? A. Atoms are smaller than the wavelength of visible light. B. Atoms are mostly empty space, just as the solar system is mostly empty space. C. Atoms are perpetually moving. D. Atoms are manufactured in plants, and in humans during pregnancy. E. All are correct.

b. neon

Which of the following is a gas? a. sodium b. neon c. lithium d. carbon

a. there are only about 100 different kinds of atoms that combine to form all substances

Which of the following statements is true? a. there are only about 100 different kinds of atoms that combine to form all substances b. a large atom can be photographed with the aid of an ordinary microscope c. an atom is the smallest particle known to exist d. none of the above

c. uranium

Which of these atoms has the greatest number of electrons? a. helium b. gold c. uranium d. carbon e. iron

b. lead

Which of these has the greatest number of protons in its nucleus? a. silver b. lead c. gold d. mercury

Aristotle

Which of these investigators did NOT contribute to our knowledge of atoms?

john dalton

Who advanced the idea of atoms in the early 1800s?

Albert Einstein

Who first explained Brownian motion and made a convincing case for the existence of atoms?

The larger positive charge in the nucleus pulls the electrons into closer orbits.

Why aren't heavier elements much larger than lighter elements?

The wavelength of the electrons is smaller than an atom.

Why can atoms be seen with an electron beam?

Atoms are much smaller than a wavelength of light.

Why can't atoms be seen with a powerful optical microscope?

a proton or a neutron

what is meant by the term nucleon

A model is an abstraction that helps us visualize and predict.

what is the purpose if a model in science?