Conceptual Physics Ch 11

In our part of the universe, antimatter is A) short-lived. B) long-lived. C) non-existent. D) plentiful.

A) short-lived.

What makes an element distinct? A) the number of protons B) the total mass of all the particles C) the number of neutrons D) none of these E) the number of electrons

A) the number of protons

How many different elements are in a water molecule? A) two B) none C) four D) three E) one

A) two

Which of these atoms has the most mass? A) uranium B) lead C) hydrogen D) iron

A) uranium

amu

Abbreviation for atomic mass unit.

antiproton

Antiparticle of a proton; a negatively charged proton.

A nucleus with an atomic number of 44 and a mass number of 100 must have A) 44 neutrons. B) 56 neutrons. C) 100 neutrons. D) All of the above.

B) 56 neutrons.

Brownian motion provided some evidence for the existence of atoms because A) the atoms were observed to be jiggling around. B) the jiggling of small dust grains indicated that very small particles (atoms) are colliding with the grains.

B) the jiggling of small dust grains indicated that very small particles (atoms) are colliding with the grains.

Which of these statements is true? A) A molecule is the smallest particle that exists. B) Chemical elements are made up of about 100 distinct molecules. C) Atoms are the smallest subdivision of matter that retains the chemical properties of a substance. D) Molecules form atoms that in turn determine chemical properties of a substance

C) Atoms are the smallest subdivision of matter that retains the chemical properties of a substance.

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.

C) Both of the above.

periodic table

Chart that lists elements by atomic number and by electron arrangements, so that elements with similar chemical properties are in the same column (group).

oxidize

Chemical process in which an element or molecule loses one or more electrons.

compound

Chemical substance made of atoms of two or more different elements combined in a fixed proportion.

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.

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

The smallest particle of those listed below is A) a molecule. B) an atom. C) a neutron. D) a quark. E) a proton.

D) a quark.

The air in this room has A) mass. B) weight. C) energy. D) all of these E) none of these

D) all of these

Atoms heavier than helium were made by A) radiant energy conversion. B) photosynthesis. C) radioactivity. D) thermonuclear fusion.

D) thermonuclear fusion.

chemical formula

Description that uses numbers and symbols of elements to describe the proportions of elements in a compound or reaction.

Which of the following is not a mixture? A) granite B) cake C) air D) beach sand E) None. All of the above choices are mixtures.

E) None. All of the above choices are mixtures.

A force that determines the chemical properties of an atom is a(n A) gravitational force. B) none of these C) nuclear force. D) friction force. E) electrical force.

E) electrical force.

neutron

Electrically neutral particle that is one of the two kinds of nucleons that compose an atomic nucleus.

meson

Elementary particle with an atomic weight of zero; can participate in the strong interaction.

Brownian motion

Haphazard movement of tiny particles suspended in a gas or liquid resulting from bombardment by the fast-moving molecules of the gas or liquid.

antimatter

Matter composed of atoms with negative nuclei and positive electrons.

electron

Negative particle in the shell of an atom.

If a 1·gram body of antimatter meets a 10·gram body of matter, what mass survives?

Nine grams of matter survive (the other 2 grams are transformed into radiant energy)

atomic mass number

Number associated with an atom, equal to the number of nucleons (protons plus neutrons) in the nucleus.

antiparticle

Particle having the same mass as a normal particle, but a charge of the opposite sign. The antiparticle of an electron is a positron.

proton

Positively charged particle that is one of the two kinds of nucleons in the nucleus of an atom.

chemical reaction

Process of rearrangement of atoms that transforms one molecule into another.

Which contributes more to an atom's mass, electrons or protons?

Protons contribute more to an atom's mass.

Is common table salt an element, a compound, or a mixture?

Pure table salt is a compound of the elements sodium and chlorine. Jn a strict sense, common table salt is a mixture -often with small amounts of potassium iodide and sugar. The iodine in the potassium iodide has virtually eliminated a common affliction of earlier times, a swelling of the thyroid gland known as endemic goiter. Tiny amounts of sugar prevent oxidation of the salt, which otherwise would turn yellow.

Are there really atoms that were once a part of Albert Einstein incorporated in the brains of all the members of your family?

Quite so. However, these atoms are combined differently than they were previously. Our atoms are immortal.

Mach number

Ratio of the speed of an object to the speed of sound. For example, an aircraft traveling at the speed of sound is rated Mach 1.0; traveling at twice the speed of sound, Mach 2.0.

atom

Smallest particle of an element that has all the element's chemical properties. Consists of protons and neutrons in a nucleus surrounded by electrons.

atomic mass unit (amu)

Standard unit of atomic mass. It is based on the mass of the common carbon atom, which is arbitrarily given the value of exactly 12. An amu of 1 is one-twelfth the mass of this common carbon atom.

neutron star

Star that has undergone a gravitational collapse in which electrons are compressed into protons to form neutrons.

element

Substance composed of atoms that all have the same atomic number and, therefore, the same chemical properties.

mixture

Substances mixed together without combining chemically.

Which are older, the atoms in the body of an elderly person or those in the body of a baby'

The age of the atoms in both is the same. Most of the atoms were manufactured in stars that exploded before the solar system came into existence.

What fundamental force dictates the size of an atom?

The electrical force.

World population grows each year. Does this mean that the mass of Earth increases each year?

The greater number of people increases the mass of Earth by zero. The atoms that make up our bodies are the same atoms that were here before we were born-we are but dust. and unto dust we shall return. The materials that make up human cells are rearrangements of material already present. The atoms that make up a baby forming in its mother's womb are supplied by the food the mother eats. And those atoms originated in stars-some of them in far-away galaxies. (Interestingly, the mass of Earth does increase by the incidence of roughly 40,000 tons of interplanetary dust each year, but not by the birth and survival of more people.)

tau

The heaviest elementary particle in the class of elementary particles called leptons.

Which is represented by a whole number- the mass number or the atomic mass?

The mass number is always given as a whole number, such as hydrogen-lor carbon-12. Atomic mass, by contrast, is the average mass of the various isotopes of ar element and is thus represented by a fractional number,

Do two isotopes of iron have the same atomic number?

The two isotopes of iron have the same atomic number 26, because they each have 26 protons in the nucleus. They have different atomic mass numbers if they have different numbers of neutrons in the nucleus.

How many atomic nuclei are in a single oxygen atom? In a single oxygen molecule?

There is one nucleus in an oxygen atom, O, and two in the combination of two oxygen atoms-an oxygen molecule, O2

Do two isotopes of iron have the same atomic mass number?

They have different atomic mass numbers if they have different numbers of neutrons in the nucleus.

molecule

Two or more atoms of the same or different elements bonded to form a larger particle.

dark matter

Unseen and unidentified matter that is evident by its gravitational pull on stars in the galaxies.

positron

antiparticle of an electron; a positively charged electron.

ion

atom (or group of atoms bound together) with a net electric charge, which is due to the loss or gain of electrons.

negative ion

atom or group of atoms that has a negative charge.

positive ion

atom or group of atoms that has a positive charge

isotopes

atoms whose nuclei have the same number of protons but different number of neutrons.

nuetron

electrically neutral particle that is one of the two kinds of nucleons that compose an atomic nucleus.

Which contributes more to an atom's volume (its size)!

electrons contribute more to its size.

atomic number

number associated with an atom, equal to the number of protons in the nucleus, or, equivalently, to the number of electrons in the electron cloud of a neutral atom.

microscope

optical instrument that forms enlarged images of very small objects.

model

physical representation of an idea created to make the idea more understandable.

free radical

unbonded, electrically neutral, very chemically active atom or molecular fragment.