An atom of an element with atomic number 48 and mass number 120 contains

48 protons, 48 electrons, and 72 neutrons

Which of these statements is not true?

Isotopes of an element have different numbers of protons

The nucleus of an atom is

Positively charged and has a high density.

studbud

Gen Chem - Ch 3 - Atomic Structure

20 termsStudBud Administration258 plays

Ch 3 - Atomic structure. Review of history and atomic basics.

Flashcards20 cardsFPractice quizPHost liveL

Questions 20

Answers

1
An atom of an element with atomic number 48 and mass number 120 contains
120 protons, 48 electrons, and 72 neutrons
48 protons, 48 electrons, and 72 neutrons
72 protons, 48 electrons, and 48 neutrons
72 protons, 72 electrons, and 48 neutrons
2
Type of elements that tend to lose electrons.
Metals
Non-metals
Noble gases
3
The scientist who discovered the nucleus.
Rutherford
Dalton
Democritus
Mendeleev
4
A mole of an element is worth
6.022 x 1023 atoms
6.022 x 1023 electrons
6.022 x 1023 grams
6.022 x 1023 neutrons
5
The nucleus is composed of:
protons & neutrons
Quarks
Electrons & neutrons
protons & electrons
6
The scientist who discovered the neutron.
Chadwick
Rutherford
Thomson
Dalton
7
Si has 3 isotopes - 28, 29, and 30. Its atomic mass is 28.086. Which isotope is most abundant?
30
29
28
8
This number tells us how many protons are present.
Atomic weight
Nucleus
Atomic number
Atomic Mass
9
The number 80 in the name bromine-80 represents
none of the above
atomic number
sum of protons & electrons
atomic mass
10
Which of the following is not a part of Dalton’s atomic theory?
Atoms are always in motion.
All elements are composed of atoms
Atoms that combine do so in simple whole-number ratios.
Atoms of the same element are alike.
11
A mole of an element is equal to its
number of electrons
number of protons
atomic mass
atomic number
12
Apparatus filled with inert gas, having + & - charge plates to deflect electrons.
Calorimeter
Microscope
Gold foil
Cathode ray tube
13
Which of these statements is not true?
The nucleus of an atom has a positive charge
Atoms of the same element can have different masses
Atoms are mostly empty space
Isotopes of an element have different numbers of protons
14
Who developed the concept of the mole?
Avogadro
Rutherford
Thomson
Dalton
15
The nucleus of an atom is
Negatively charged and has a low density.
Positively charged and has a high density.
Positively charged and has a low density.
Negatively charged and has a high density.
16
Isotopes have a different number of
Protons
Electrons
Neutrons
17
Atomic mass is a weighted average of
an element's atomic number
Electrons
an element's isotopes
an element's protons
18
The experiment that helped to discover the nucleus.
Gold Foil
Isotopic Decay
Radioactive Decay
Cathode Ray Tube
19
The scientist who discovered the electron
Dalton
Chadwick
Rutherford
Thomson
20
Atoms of the same element that have different numbers of neutrons
Compounds
Neutrons
Nucleotides
Isotope

Gen Chem - Ch 3 - Atomic Structure Flashcards | StudBud