Chemistry June 2019 Multiple Choice

Which particles are found in the nucleus of an argon atom?

• protons and electrons

• positrons and neutrons

• protons and neutrons

• positrons and electrons

The diagram represents a particle traveling through an electric field. Which particle remains undeflected when passing through this electric field?

• proton

• electron

• neutron

• positron

The mass of an electron is

• equal to the mass of a proton

• equal to the mass of a neutron

• greater than the mass of a proton

• less than the mass of a neutron

Compared to the energy of an electron in the second shell of an atom of sulfur, the energy of an electron in the

• first shell is lower

• first shell is the same

• third shell is lower

• third shell is the same

In the ground state, an atom of which element has seven valence electrons?

• sodium

• phosphorus

• nitrogen

• fluorine

Which information is sufficient to differentiate a sample of sodium from a sample of silver?

• the mass of each sample

• the volume of each sample

• the reactivity of each sample with water

• the phase of each sample at room temperature

Graphite and diamond are two forms of solid carbon at STP. These forms have

• different molecular structures and different properties

• different molecular structures and the same properties

• the same molecular structures and different properties

• the same molecular structures and the same properties

As the first five elements in Group 14 are considered in order from top to bottom, there are changes in both the

• number of valence shell electrons and the number of first shell electrons

• electronegativity values and number of first shell electrons

• number of valence shell electrons and atomic radii

• electronegativity values and atomic radii

Which statement explains why NaBr is classified as a compound?

• Na and Br are chemically combined in a fixed proportion.

• Na and Br are both nonmetals.

• NaBr is a solid at 298 K and standard pressure.

• NaBr dissolves in H₂O at 298 K

Which two terms represent types of chemical formulas?

• fission and fusion

• oxidation and reduction

• empirical and structural

• endothermic and exothermic