Chemistry 10- Unit 6

The charge on a proton is

+1e

The letter e represents the elementary charge. In normal matter, the charge that would NOT be found is

+2.5e

An atom contains 11 electrons. If a 12th electron were added to the atom, the energy level into which it would be placed is energy level:

3

A common isotope of Carbon has an atomic number of 6 and a mass number of 13. How many neutrons are in an atom of this isotope?

7

A common isotope of iron (Fe) has an atomic number of 26 and a mass number of 56. The total number of subatomic particles in the nucleus is:

82

Which of the following is a TRUE statement about atoms?

All atoms of the same element have the same number of electrons, but may have different number of neutrons

Of the following statements, the one which is ALWAYS TRUE is:

All lithium atoms contain the same number of protons

What is the fundamental property of matter that can either be positive or negative?

Charge

British physicist J.J. Thomas was the first to identify the:

Electron

Many models have been developed to explain the nature of atoms. The model that helped scientists to understand energy levels of atoms was developed by:

Niels Bohr

What do we call the tiny core at the center of an atom, containing most of the atoms mass and all of its positive charge?

Nucleus

The _____________ is one kind of particle that makes up the atom and carries a positive charge.

Proton

Why dont all the electrons in an atom fall to the lowest energy level?

The lowest energy level can only hold 2 electrons

When Ernest Rutherford directed helium ions at gold foil, some of the helium ions bounced back in the direction they came from, rather than passing through. What was his explanation of this unexpected results.

The mass of gold atom is concentrated in a tiny, dense core

Which of the following statements about two isotopes of the same element is FALSE?

The number of protons might be different between the two isotopes

Protons and neutrons in the nuclear are held together by:

The strong nuclear force

The "building blocks" of matter are:

atoms and molecules

Fireworks contain different elements in them for displaying different colors. The different colors occur because:

atoms of various elements emit light at different frequencies

Electrons are bound to the nucleus by

electromagnetic force

A particle with zero charge found in the nucleus of an atom is called:

electron

An atom contains _____________ in various energy levels.

electrons

Electrons with higher energy are located:

farther from the nucleus of the atom

Atoms with the same atomic number but different atomic mass are called:

isotopes

The mass of an atom is determined mainly by the:

mass of the neutrons and protons

An atom absorbs energy as its electrons:

move from a low energy level to a high energy level

An atom emits light when one of its electrons:

moves from a high energy level to a low energy level

Compare to protons, electrons have:

much smaller mass and opposite charge

Protons and neutrons are found grouped together in the:

nucleus

what to we call the tiny core at the center of a atom

nucleus

Atomic number is

the number of protons in an atom

Atoms of the same element may contain:

the same number of protons but a different number of neutrons

When an unstable isotope undergoes alpha decay, it gives off:

two protons and two neutrons

The charge on a complete atom is equal to

zero