Atomic Structure and Sig Fig/DA Test

The nucleus of an atom is:

• positively charged and has high density

• positively charged and has low density

• negatively charged and has high density

• negatively charged and has low density

The number of neutrons in the nucleus of an atom can be calculated by:

• adding together the number of electrons and protons

• subtracting the number of electrons from the number of protons

• subtracting the number of protons from the mass number

• adding the mass number to the number of electrons

Which of the following statements is false?

• protons have a positive charge

• The neutron is found in the nucleus of an atom

• Electrons are negatively charged and have a mass of 1 amu

• The nucleus of an atom is positively charged

All atoms of the same element have the same:

• number of neutrons

• number of protons

• mass numbers

• mass

An atom of an element with atomic number 50 and mass number 120 contains:

• 50 protons, 50 electrons, and 70 neutrons

• 70 electrons, 50 protons, and 50 neutrons

• 120 neutrons, 50 protons, and 70 electrons

• 70 neutrons, 70 protons, and 50 electrons

The number 84 in the name krypton-84 represents:

• the atomic number

• the mass number

• the sum of the protons and electrons

• none of these

Which of these statements is NOT true?

• Atoms are mostly empty space

• The nucleus of an atom has a positive charge

• Isotopes of atoms of an element have different numbers of protons

• Atoms of the same elements can have different numbers of neutrons

Average atomic masses are measured in:

• grams

• angstroms

• moles

• Amu

Which of the following shows the correct scientist with his contribution?

• Dalton- discovered the proton

• Rutherford- discovered orbits

• Bohr- discovered the nucleus

• Thomson- discovered the electron

Ernest Rutherford is credited with the discovery of the nucleus of the atom along with this subatomic particle.

• neutron

• electron

• proton

• orbits