Chemistry Exam

The most common element in the universe is

• nitrogen

• hydrogen

• oxygen

• aluminum

Electrons

• have a positive charge

• determine the atomic number of an element

• have more mass than the other parts of an atom

• move around outside the nucleus

One kind of uranium atom has 92 protons and 143 neutrons. Another atom of uranium has 92 protons and 146 neutrons. The two uranium atoms are different

• ions

• elements

•    electrons

• isotopes

Mg²⁺ is a magnesium ion that has

• two fewer electrons than a neutral magnesium atom

• two fewer neutrons than a neutral magnesium atom

• two more protons than a neutral magnesium atom

• an atomic mass greater than that of a neutral magnesium atom

Most elements on the periodic table are

• metalloids

• metals

• noble gases

• nonmetals

The least active elements are

• halogens

• alkali metals

• alkaline earth metals

• noble gases

Most nonmetals are

• liquid at room temperature

• poor conductors of heat

• easy to hammer and shape

• shiny in appearance

The two most common elements in the human body are

• hydrogen and oxygen

• silicon and aluminum

• oxygen and carbon

• iron and nitrogen

The nucleus of an atom contains

• protons, neutrons, and electrons

• only electrons

• protons and neutrons

• electrons and protons

Tags

NGSS.MS-PS1-1

A chlorine ion has a charge of 1-. You can infer that the ion has one

• more proton than usual

• fewer neutron than usual

• more electron than usual

• more neutron than usual